DTC table: VAG codes

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2006 Volkswagen Golf, 2005 Volkswagen Jetta, 2005 Volkswagen Golf, 2004 Volkswagen Jetta, and 2004 Volkswagen Golf. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

DTC tables are listed according to VAG code.
Explanation of DTC types (e.g. "open circuit/short circuit to ground" ): Scan Tool (ST) operating instructions
If DTCs are indicated:
Check wiring and connectors to these components as well as ground connections according to wiring diagram. This particularly applies if DTCs are displayed as "occurring sporadically" (SP).
Erase DTC memory after correcting DTC → Diagnostic Trouble Code (DTC) memory, checking and erasing and reset readiness code → Readiness code, setting .
VAG1551 print out, e.g.:
16502 P0118 035
Engine Coolant Temperature (ECT) sensor G62
Signal too high
Sporadic DTC
Explanation:
16502 = DTC code
P0118 = Additional DTC code
035 = DTC type as a number
Engine Coolant Temperature (ECT) sensor G62 = DTC current path or DTC location
Signal too high = DTC type as text
Sporadic DTCs = intermittent DTCs, e.g. loose contact

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
00668
Voltage terminal 30
	Implausible signal	Power supply (terminal 30, B+) relay J317 inoperative Relay sticks (sporadically)	Engine will not start Various running problems	Check ECM voltage supply → Diesel direct injection system voltage supply, checking
00671
Cruise Control Switch E45
	Undefined switch position	E45 inoperative Open/short circuit	Cruise control off	Check cruise control: → Electrical Wiring Diagrams, Troubleshooting and Component Locations

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
00741
Brake pedal monitoring
	Implausible signal	Brake Light Switch F inoperative Cruise Control/Diesel Direct Fuel Injection (DFI) Brake Pedal Switch F47 inoperative	Glow Plug Indicator Light K29 blinks Brake light inoperative	Check F Brake Light Switch F and Brake Pedal Switch F47 → Brake light switch F and Brake Pedal Switch F47 , checking
01044
Control Module incorrectly coded (no display)
		Invalid Control Module code	Glow Plug Indicator Light K29 blinks	Code Control Module → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , coding
01117
Load signal for Generator terminal DF
	Implausible signal	Generator (GEN) inoperative Voltage regulator inoperative Open circuit	Engine warm-up (preheat) inoperative	Check GEN: → Electrical Wiring Diagrams, Troubleshooting and Component Locations

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
01193
Pre Heating Coolant/Low Heat Output Relay J359
	Short to positive (B+)	J359 inoperative Open circuit or short to positive (B+)	Engine preheat inoperative	Check J359 → Function 03: Output Diagnostic Test Mode (DTM) , Output Diagnostic Test Mode
01194
Pre Heating Coolant/High Heat Output Relay J360
	Short to positive (B+)	J360 inoperative Open circuit or short to positive (B+)	Engine preheat inoperative	Check J360 → Function 03: Output Diagnostic Test Mode (DTM) , Output Diagnostic Test Mode
01282
Change-over valve for Intake manifold flap N239 -
	Open circuit/short to ground	N239 inoperative Wiring open circuit or short to ground	Abrupt engine stop	Check intake manifold change-over flap N239 → Intake Manifold Flap Change-over Valve N239 , checking
	Short to positive (B+)	Short to positive (B+)

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16485 P0101
Mass Air Flow (MAF) Sensor G70
	Signal too low	G70 inoperative Open circuit/short to positive (B+)	Reduced power Black smoke	Check Mass Air Flow (MAF) Sensor G70 → Mass Air Flow (MAF) sensor G70 , checking
16486 P0102
Mass Air Flow (MAF) Sensor G70
	Signal too low	Mass Air Flow (MAF) Sensor G70 inoperative Open circuit/short to positive (B+)	Reduced power Black smoke	Check Mass Air Flow (MAF) Sensor G70 → Mass Air Flow (MAF) sensor G70 , checking
16487 P0103
Mass Air Flow (MAF) Sensor G70
	Signal too high	G70 inoperative Open circuit/short to ground	Reduced power Black smoke	Check Mass Air Flow (MAF) Sensor G70 → Mass Air Flow (MAF) sensor G70 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16489 P0105
Manifold Absolute Pressure (MAP) Sensor G71
	Voltage supply	Manifold Absolute Pressure (MAP) Sensor G71 inoperative Wiring open circuit or short circuit	Reduced output Increased emission figures	Check Manifold Absolute Pressure (MAP) Sensor → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking
16490 P0106
Manifold Absolute Pressure (MAP) Sensor G71
	Implausible signal	Manifold Absolute Pressure (MAP) Sensor G71 inoperative Wiring open circuit or short to ground	Reduced output Increased emission figures	Check Manifold Absolute Pressure (MAP) Sensor → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16491 P0107
Manifold Absolute Pressure (MAP) Sensor G71
	Signal too low	Manifold Absolute Pressure (MAP) Sensor G71 inoperative Wiring open circuit or short to ground	Reduced output Increased emission figures	Check Manifold Absolute Pressure (MAP) Sensor → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking
16492 P0108
Manifold Absolute Pressure (MAP) Sensor G71
	Signal too high	Manifold Absolute Pressure (MAP) Sensor G71 inoperative Wiring open circuit or short to ground	Reduced output Increased emission figures	Check Manifold Absolute Pressure (MAP) Sensor → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking
16500 P0116
Engine Coolant Temperature Sensor G62
	Implausible signal	Engine Coolant Temperature (ECT) sensor G62 inoperative	Black smoke when starting Glow period is always approx. 20 seconds	Check Engine Coolant Temperature (ECT) sensor G62 → Engine Coolant Temperature (ECT) sensor G62 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16501 P0117
Engine Coolant Temperature Sensor G62
	Signal too low	Engine Coolant Temperature (ECT) sensor G62 inoperative Wiring open circuit or short to ground	Black smoke during start Glow period always takes about 20 seconds	Check Engine Coolant Temperature (ECT) sensor G62 → Engine Coolant Temperature (ECT) sensor G62 , checking
16502 P0118
Engine Coolant Temperature Sensor G62
	Signal too high	Engine Coolant Temperature (ECT) sensor G62 inoperative Wiring open circuit or short to positive (B+)	Black smoke during start Glow period always takes about 20 seconds	Check Engine Coolant Temperature (ECT) sensor G62 → Engine Coolant Temperature (ECT) sensor G62 , checking
16566 P0182
Fuel temperature sensor G81
	Short to ground	Fuel Temperature Sensor G81 inoperative Wiring short to ground	Goes to predetermined value - 5.4 ° C Increased emission figure	Check Fuel Temperature Sensor G81 - → Fuel temperature sensor G81 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16567 P0183
Fuel temperature sensor G81
	Open/Short to positive (B+)	Fuel Temperature Sensor G81 inoperative Wiring open circuit or short to positive (B+)	Goes to predetermined value - 5.4 ° C Increased emission figure	Check Fuel Temperature Sensor G81 - → Fuel temperature sensor G81 , checking
16600 P0216
Cold Start Injector N108
	Malfunction	Wiring open circuit Cold Start Injector valve inoperative	Engine knocks at idle, because commencement of injection is constantly "advanced"	Check Cold Start Injector N108 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
		Short to ground	Poor performance, because commencement of injection is constantly "retarded"

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16609 P0225
Throttle Position (TP) Sensor G79
	Voltage supply	Operating voltage too high or too low Wiring open circuit	Glow period warning lamp flashes Increased idle speed	Check Throttle Position (TP) Sensor G79 → 20 - FUEL SUPPLY
16610 P0226
Throttle Position (TP) Sensor G79
	Implausible signal	Throttle Position (TP) Sensor G79 defective	Increased idle speed	Check Throttle Position (TP) Sensor G79 → 20 - FUEL SUPPLY

* Incorrect fault text display. Display must indicate: Throttle Position (TP) Sensor G79 implausible signal

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16612 P0228
Throttle Position (TP) Sensor G79
	Signal too high	Throttle Position (TP) Sensor G79 defective	Increased idle speed	Check Throttle Position (TP) Sensor G79 → 20 - FUEL SUPPLY

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16618 P0234
Boost pressure control
	Control limit exceeded	Hose connections interchanged, not attached	Boost pressure too high Reduced output	Check Wastegate Bypass Regulator Valve N75 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode Check charge pressure control
16629 P0245
Wastegate Bypass Regulator Valve N75
	Open circuit/short to ground	Wiring open circuit Solenoid valve defective	Reduced output Boost pressure too low	Check Wastegate Bypass Regulator Valve N75 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
		Short to ground	Reduced output Boost pressure too high

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16630 P0246
Wastegate Bypass Regulator Valve N75
	Short to positive	Short to positive	Reduced output Boost pressure too low	Check Wastegate Bypass Regulator Valve N75 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
16684 P0300
Misfiring detected
		No combustion in one or more cylinders No compression pressure	Reduced output Engine runs rough Increased emission figures	Check compression pressure → 15 - ENGINE - CYLINDER HEAD, VALVETRAIN

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16685 P0301
Misfiring recognized
	No. 1 Cyl.	No combustion in No. 1 Cyl. No compression pressure	Reduced output Engine runs rough Increased emission figures	Check compression pressure → 15 - ENGINE - CYLINDER HEAD, VALVETRAIN
16686 P0302
Misfiring recognized
	No. 2 Cyl.	No combustion in No. 2 Cyl. No compression pressure

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16687 P0303
Misfiring recognized
	No. 3 Cyl.	No combustion in No. 3 Cyl. No compression pressure	Reduced output Engine runs rough Increased emission figures	Check compression pressure → 15 - ENGINE - CYLINDER HEAD, VALVETRAIN
16688 P0304
Misfiring recognized
	No. 4 Cyl.	No combustion in No. 4 Cyl. No compression pressure

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16705 P0321
Engine RPM Sensor G28 -
	Implausible signal	G28 inoperative RPM sensor/sensor wheel gap too wide Metal chips on G28 or retaining base loose	Engine will not start Engine stalls Glow Plug Indicator Lamp K29 flashes Speedometer inoperative	Check Engine RPM Sensor G28 → Engine Speed (RPM) Sensor G28 , checking
16706 P0322
Engine RPM Sensor G28
	No signal	G28 inoperative Open/short circuit	Engine will not start Engine stalls Glow Plug Indicator Lamp K29 flashes Speedometer inoperative	Check Engine RPM Sensor G28 → Engine Speed (RPM) Sensor G28 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16785 P0401
Exhaust gas recirculation (EGR) system
	Gas flow too low	Short to positive (B+) EGR vacuum regulator solenoid valve malfunction	No EGR	Check EGR Vacuum Regulator Solenoid Valve N18 - → Performing Output Diagnostic Test Mode , Performing Output Diagnostic Test Mode
16786 P0402
Exhaust gas recirculation (EGR) system
	Gas flow too high	Short to positive (B+) EGR vacuum regulator solenoid valve malfunction	No EGR	Check EGR Vacuum Regulator Solenoid Valve N18 - → Performing Output Diagnostic Test Mode , Performing Output Diagnostic Test Mode

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
16885 P0501
Vehicle Speed Signal (VSS)
	Implausible signal	No signal from Speedometer Vehicle Speed (VSS) Sensor G22	Speedometer display inoperative Cruise control off Vehicle jerks when changing gear Air conditioner off	Check Speedometer Vehicle Speed (VSS) sensor → Additional signals, checking
16955 P0571
Brake light switch - F
	Implausible signal	Brake light switch F defective Brake pedal switch F47 defective	Glow period warning lamp flashes Brake light defective	Check Brake light switch F and Brake pedal switch F47 → Brake light switch F and Brake Pedal Switch F47 , checking

DTC VAG1551 display	Possible causes	Possible effects	Corrective action
16985 P0601
Engine Control Module (ECM) J248 inoperative	ECM inoperative	Various running problems Engine stops	Replace Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing
16989 P0605
Engine Control Module (ECM) J248 inoperative	ECM inoperative	Various running problems Engine will not start	Replace Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing
16990 P0606
Engine Control Module (ECM) J248 inoperative	ECM inoperative	Various running problems Engine stops	Replace Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17054 P0670
Glow Period Control Module J370 , electrical circuit
	Malfunction in electrical circuit	Wiring open circuit or short to ground J370 inoperative	No glow period Poor cold starting	Check Glow Plug Activation Control Module J370
17055 P0671
Glow plug cyl. 1
	Malfunction in electrical circuit	Wiring open circuit or short to ground Glow plug inoperative	No glow period Poor cold starting	Check glow plug system → Glow plug system, checking
17056 P0672
Glow plug cyl. 2
	Malfunction in electrical circuit	Wiring open circuit or short to ground Glow plug inoperative	No glow period Poor cold starting	Check glow plug system → Glow plug system, checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17057 P0673
Glow plug cyl. 3
	Malfunction in electrical circuit	Wiring open circuit or short to ground Glow plug inoperative	No glow period Poor cold starting	Check glow plug system → Glow plug system, checking
17058 P0674
Glow plug cyl. 4
	Malfunction in electrical circuit	Wiring open circuit or short to ground Glow plug inoperative	No glow period Poor cold starting	Check glow plug system → Glow plug system, checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17068 P0684
Glow Period Control Module J370
	Implausible signal	No connection to Engine Control Module Glow Plug Activation Control Module J370 defective	No glow period Poor cold starting	Check Glow Plug Activation Control Module J370
17552 P1144
Mass Air Flow (MAF) Sensor G70
	Open circuit/short to ground	Mass Air Flow (MAF) Sensor G70 inoperative Open circuit/short to ground	Reduced power Black smoke	Check Mass Air Flow (MAF) Sensor G70 → Mass Air Flow (MAF) sensor G70 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17553 P1145
Mass Air Flow (MAF) Sensor G70
	Short to positive (B+)	Mass Air Flow (MAF) Sensor G70 inoperative Open circuit/short to positive (B+)	Reduced power Black smoke	Check Mass Air Flow (MAF) Sensor G70 → Mass Air Flow (MAF) sensor G70 , checking
17554 P1146
Mass Air Flow (MAF) Sensor G70
	Supply voltage	Operating voltage too high or too low Open circuit	Reduced power Black smoke	Check Mass Air Flow (MAF) Sensor G70 → Mass Air Flow (MAF) sensor G70 , checking
17563 P1155
Manifold Absolute Pressure (MAP) Sensor G71
	Short to positive (B+)	Manifold Absolute Pressure (MAP) Sensor G71 inoperative Short to positive (B+)	Reduced power	Check Manifold Absolute Pressure (MAP) Sensor G71 → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17564 P1156
Manifold Absolute Pressure (MAP) Sensor G71
	Open circuit/short to ground	Manifold Absolute Pressure (MAP) Sensor G71 inoperative Open circuit/short to ground	Reduced power Increased emission values	Check Manifold Absolute Pressure (MAP) Sensor G71 → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking
17565 P1157
Manifold Absolute Pressure (MAP) Sensor G71
	Supply voltage	Manifold Absolute Pressure (MAP) Sensor G71 inoperative Open circuit/short circuit	Reduced power Increased emission values	Check Manifold Absolute Pressure (MAP) Sensor G71 → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking
17566 P1158
Manifold Absolute Pressure (MAP) Sensor G71
	Implausible signal	Manifold Absolute Pressure (MAP) Sensor G71 inoperative	Reduced power Increased emission values	Check Manifold Absolute Pressure (MAP) Sensor G71 → Manifold Absolute Pressure (MAP) sensor G71 and Barometric Pressure (BARO) sensor F96 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17568 P1160
Intake Air Temperature (IAT) Sensor G72
	Short to ground	Intake Air Temperature (IAT) Sensor G72 inoperative Short to ground	Constant temperature of 136.8 ° C (275 ° F)	Check Intake Air Temperature (IAT) Sensor G72 → Checking intake manifold temperature sensor
17569 P1161
Intake Air Temperature (IAT) Sensor G72
	Open circuit/short to positive (B+)	Intake Air Temperature (IAT) Sensor G72 inoperative Open circuit or short to positive (B+)	Goes to constant temperature of 136.8 ° C (275 ° F) Engine glow period inoperative	Check Intake Air Temperature (IAT) Sensor G72 → Checking intake manifold temperature sensor
17570 P1162
Fuel Temperature Sensor G81
	Short to ground	G81 inoperative Short to ground	Increased emission values	Check Fuel Temperature Sensor G81 - → Fuel temperature sensor G81 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17571 P1163
Fuel Temperature Sensor G81
	Open circuit/short to positive (B+)	G81 inoperative Open circuit/short to positive (B+)	Goes to predetermined value - 5.4 ° C Increased emission values	Check Fuel Temperature Sensor G81 - → Fuel temperature sensor G81 , checking
17572 P1164
Fuel Temperature Sensor G81
	Implausible signal	G81 inoperative Wiring open circuit	Increased emission values	Check Fuel Temperature Sensor G81 - → Fuel temperature sensor G81 , checking
17653 P1245
Needle Lift Sensor G80
	Short to ground	G80 inoperative Short to ground	Glow Plug Indicator Lamp K29 flashes Engine runs rough Reduced power Increased emission values	Check Needle Lift Sensor G80 → Needle lift sensor G80 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17654 P1246
Needle Lift Sensor G80
	Implausible signal	G80 inoperative No. 3 Cyl. injector line damaged Fuel shortage Air in fuel system	Glow Plug Indicator Lamp K29 flashes Engine runs rough Reduced power Increased emission values	Check Needle Lift Sensor G80 → Needle lift sensor G80 , checking
17655 P1247
Needle Lift Sensor G80
	Open circuit/short to positive (B+)	G80 inoperative Open circuit/short circuit	Glow Plug Indicator Lamp K29 flashes Engine runs rough Reduced power Increased emission values	Check Needle Lift Sensor G80 → Needle lift sensor G80 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17656 P1248
Cold Start Injector N108
	Control difference	Cold Start Injector N108 inoperative Needle Lift Sensor G80 Fuel tank empty Fuel supply low Start of delivery not OK.	Engine runs rough Reduced power Increased emission values Poor cold start	Check Cold Start Injector N108 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode Check Needle Lift Sensor G80 → Needle lift sensor G80 , checking Check and adjust injection start control dynamically → Start of injection, dynamically checking and adjusting Fuel filter or fuel line blocked

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17659 P1251
Cold Start Injector N108
	Short to positive (B+)	Short to positive (B+)	Engine knocks at idle, start of injection is "advanced" continuously	Check Cold Start Injector N108 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
17660 P1252
Cold Start Injector N108
	Open circuit/short to ground	N108 inoperative Open circuit	Engine knocks at idle, cold start is "advanced" continuously	Check Cold Start Injector N108 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
		Short to ground	Poor performance, start of injection is "advanced" continually

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17663 P1255
Engine Coolant Temperature (ECT) Sensor G62
	Short to ground	G62 inoperative Short to ground	Black smoke when starting Glow period is always approx. 20 seconds	Check Engine Coolant Temperature (ECT) sensor G62 → Engine Coolant Temperature (ECT) sensor G62 , checking
17664 P1256
Engine Coolant Temperature (ECT) Sensor G62
	Open circuit/short to positive (B+)	G62 inoperative Open circuit or short to positive (B+)	Black smoke when starting Glow period is always approx. 20 seconds	Check Engine Coolant Temperature (ECT) sensor G62 → Engine Coolant Temperature (ECT) sensor G62 , checking
17762 P1354
Modulating Piston Displacement Sensor G149
	Electrical malfunction in circuit	Injection pump inoperative Open/short circuit	Glow Plug Indicator Lamp K29 flashes Various running problems Engine will not start	Check Modulating Piston Displacement Sensor G149 - → Modulating piston displacement sensor G149 and quantity adjuster N146 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17795 P1387
Engine Control Module (ECM) J248 inoperative		ECM inoperative	Various running problems Engine will not start	Replace ECM J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing
17810 P1402
EGR Vacuum Regulator Solenoid Valve N18
	Short to positive (B+)	Short to positive (B+)	No EGR	Check EGR Vacuum Regulator Solenoid Valve N18 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
17811 P1403
Exhaust Gas Recirculation (EGR) system
	Control difference	Unmetered air Hose connections interchanged, disconnected EGR Valve inoperative (valve sticking, diaphragm rod does not move)	Reduced power Black smoke Too little or too much EGR	Check EGR: → 26 - EXHAUST SYSTEM, EMISSION CONTROLS

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17849 P1441
EGR Vacuum Regulator Solenoid Valve N18
	Open circuit/short to ground	Open circuit N18 inoperative	No EGR	Check EGR Vacuum Regulator Solenoid Valve N18 - → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
		Short to ground	Too much EGR Reduced power Black smoke

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17911 P1503
Load signal from alternator DF terminal
	Implausible signal	Alternator defective Voltage regulator defective Wiring open circuit	Engine pre-heating not operating	Check alternator → Electrical Wiring Diagrams, Troubleshooting and Component Locations
17945 P1537
Fuel Cut-off Valve N109
	Incorrect function	N109 inoperative, leaking or sticking	Reduced power Engine will not start	Check Fuel Cut-off Valve N109 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17946 P1538
Fuel Cut-off Valve N109
	Open circuit/short to ground	N109 inoperative Open circuit/short to ground	Reduced power Engine will not start	Check Fuel Cut-off Valve N109 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
17948 P1540
Road speed signal
	Signal too high	Road speed more than 260 km/h (162 mph) Dash panel insert defective	Speedometer display inoperative Cruise control system switched off Vehicle jerks when selecting gear Air conditioner is switched off	Check signal from G22 → Speed signal, testing

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17954 P1546
Wastegate Bypass Regulator valve N75
	Short to positive (B+)	Short to positive (B+)	Reduced power Boost pressure too low	Check Wastegate Bypass Regulator valve N75 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
17957 P1549
Wastegate By-pass Regulator valve N75
	Open circuit/short to ground	Wastegate Bypass Regulator valve N75 inoperative Open circuit	Reduced power Boost pressure too low	Check Wastegate Bypass Regulator valve N75 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
		Short to ground	Reduced power Boost pressure too high

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17958 P1550
Boost pressure
	Control difference	Wastegate Bypass Regulator valve N75 inoperative Hose connections interchanged, disconnected	Reduced power	Check Wastegate Bypass Regulator valve N75 - → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode Check boost pressure control → 21 - TURBOCHARGER, G-CHARGER

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17964 P1556
Boost pressure control
	Control limit not reached	Wastegate Bypass Regulator valve N75 inoperative Turbocharger defective Leaks between turbocharger and engine (boost air path)	Boost pressure too low Reduced output	Check Wastegate Bypass Regulator valve N75 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode Check boost pressure control → 21 - TURBOCHARGER, G-CHARGER
17965 P1557
Charge pressure control
	Control limit exceeded	Hose connections interchanged, not attached	Charge pressure too high Reduced output

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17969 P1561
Quantity Adjuster N146
	Control difference	Injection pump inoperative Open/short circuit	Glow Plug Indicator Lamp K29 flashes Various running problems Engine will not start	Check Quantity Adjuster N146 → Modulating piston displacement sensor G149 and quantity adjuster N146 , checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
17970 P1562
Quantity adjuster N146
	Upper stop value	Quantity adjuster N146 inoperative/blocked Upper stop value obtained	Reduced power Jerking	Check Quantity Adjuster N146 → Modulating piston displacement sensor G149 and quantity adjuster N146 , checking
17971 P1563
Quantity adjuster N146
	Lower stop value	N146 inoperative/blocked Lower stop value obtained	Black smoke Rough idle	Check Quantity Adjuster N146 → Modulating piston displacement sensor G149 and quantity adjuster N146 , checking
17977 P1569
Cruise Control Switch E45
	Implausible signal	Cruise Control Switch E45 - inoperative Wiring open/short circuit	Cruise control system is switched off	Check cruise control system → 27 BATTERY, STARTER, GENERATOR, CRUISE CONTROL

DTC VAG1551 display

Possible causes

Possible effects

Corrective action

17978 P1570

Engine Control Module blocked

Start attempted with a non-authorized button.
Attempted manipulation

Short in communication wire
Incorrect coding

Malfunction in immobilizer system
Immobilizer control module defective/missing

Engine Control Module has been replaced and not matched to the immobilizer.

Engine starts briefly and then stops again
Glow period warning lamp flashes

Match Engine Control Module to electronic immobilizer.
Check electronic immobilizer: → Diagnostic Trouble Code (DTC) memory, checking and erasing and → 01 ON BOARD DIAGNOSTIC (OBD)

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18008 P1600
Supply voltage terminal 15
	Voltage too low	No voltage supply when ignition is on (terminal 15)	Various running problems Engine will not start	Check voltage supply of Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing , and → Electrical Wiring Diagrams, Troubleshooting and Component Locations

DTC VAG1551 display	Possible causes	Possible effects	Corrective action
18009 P1601
Power Supply (Terminal 30, B+) Relay J317	Power Supply (Terminal 30, B+) Relay J317 defective Relay stuck (sporadic)	Engine does not start Various running problems until engine stops	Check voltage supply of Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing
18017 P1609
Crash switch-off triggered	Airbag triggered		→ 01 ON BOARD DIAGNOSTIC (OBD)
18020 P1612
Engine Control Module (ECM) J248 incorrectly coded
	Invalid ECM code	Glow Plug Indicator Lamp K29 flashes	Code ECM J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18024 P1616
Glow Plug Indicator Lamp K29
	Short to positive (B+)	Short to positive (B+)	Glow Plug Indicator Lamp K29 inoperative	Check Glow Plug Indicator Lamp K29 → Performing Output Diagnostic Test Mode , Performing Output Diagnostic Test Mode

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18025 P1617
Glow Plug Indicator Lamp K29
	Open circuit/short to ground	Open circuit Bulb inoperative	Glow Plug Indicator Lamp K29 inoperative	Check Glow Plug Indicator Lamp K29 → Performing Output Diagnostic Test Mode , Performing Output Diagnostic Test Mode
		Short to ground	Glow Plug Indicator Lamp K29 on continuously
18026 P1618
Glow Plug Relay J52
	Short to positive (B+)	J52 inoperative Short to positive (B+)	No glow period Poor cold starting Glow Plug Indicator Lamp K29 flashes	Check Glow Plug Relay J52 → Performing Output Diagnostic Test Mode , Performing Output Diagnostic Test Mode

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18027 P1619
Glow Plug Relay J52
	Open circuit/short to ground	J52 inoperative Open circuit/short to ground	No glow period Poor cold starting Glow Plug Indicator Lamp K29 flashes	Check Glow Plug Relay J52 → Performing Output Diagnostic Test Mode , Performing Output Diagnostic Test Mode

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18034 P1626
Drive train data bus
	Communication from gearbox control module missing	Malfunction in Transmission Control Module J217	Various running problems (gear change jolts, load change jolts)	Check CAN-Bus → CAN-bus, checking
		Malfunction in Transmission Control Module J217	TCM in emergency run mode (default)	Check automatic transmission control module (TCM) → 01 ON BOARD DIAGNOSTIC (OBD)
18039 P1631
Throttle Position (TP) Sensor G79
	Signal too high	G79 malfunction	Glow Plug Indicator Lamp K29 flashes Increased idle speed	Check Throttle Position Sensor G79 , 20 - FUEL SUPPLY , Throttle sensor, checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18040 P1632
Throttle Position (TP) Sensor G79
	Supply voltage	Voltage too high or too low Open circuit	Glow Plug Indicator Lamp K29 flashes Increased idle speed	Check Throttle Position Sensor G79 , 20 - FUEL SUPPLY , Throttle sensor, checking
18044 P1636
Drive train CAN-bus
	No message from airbag control module	Malfunction in data wire to airbag control module		Checking matching resistor of CAN-bus → CAN-bus, checking Check Airbag system: → 01 ON BOARD DIAGNOSTIC (OBD)

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18047 P1639
Throttle Position (TP) Sensor 1/2 G79 + sensor 2 G185 * See note
	Implausible signal	G79 inoperative	Increased idle speed	Check Throttle Position Sensor G79 , 20 - FUEL SUPPLY ; Throttle sensor, checking
18048 P1640
Engine Control Module (ECM) J248 inoperative		ECM J248 malfunction	Various running problems Engine will not start	Replace ECM J248 → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing
18050 P1642
Check airbag control module DTC memory		Malfunction in airbag system	Airbag warning lamp lights up	→ 01 ON BOARD DIAGNOSTIC (OBD)

* Incorrect fault text display. Display must indicate: Accelerator pedal position sender G79 implausible signal

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18056 P1648
Drive train CAN-Bus
	System component inoperative	Malfunction in CAN-Bus circuit to transmission or ABS Control Module J104	Various running problems (gear change jolts, load change jolts) No electronic control	Check CAN-Bus → CAN-bus, checking
18057 P1649
Drive train CAN-Bus
	Implausible signal from ABS Control Module J104	Malfunction in CAN-Bus circuit to ABS Control Module J104	No electronic control	Check CAN-Bus → CAN-bus, checking
		Malfunction in system (disconnected Control Module for ABS, ABS incorrectly coded)		Check ABS control module → 01 ON BOARD DIAGNOSTIC (OBD)

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18058 P1650
Drive train CAN-bus
	No message from instrument cluster	Malfunction in data wire to instrument cluster		Check CAN-Bus → CAN-bus, checking
18061 P1653
Check DTC memory of the ABS control module		Malfunction in ABS control module	No electronic stability program No TCS function No EBC function	→ 01 ON BOARD DIAGNOSTIC (OBD)
18062 P1654
Interrogate combi-instrument fault memory		Oil level/temperature sender defective	Oil level warning lamp lights up	→ 01 ON BOARD DIAGNOSTIC (OBD)

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
18065 P1657
Air conditioner input/output
	Short to positive (B+)	Short in the wiring	Vehicle acceleration reduced, when air conditioner is switched on	Check air conditioner compressor cut-in → Performing Output Diagnostic Test Mode , Output Diagnosis Test Mode (DTM)
18090 P1682
Drive train CAN-bus
	Implausible message from ABS control module	Malfunction in data wiring to ABS control module	No electronic stability control No TCS function No EBC function	Checking matching resistor of CAN-bus → CAN-bus, checking

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
19456 P3000
Glow period warning lamp K29
	Malfunction message from instrument cluster	Malfunction in CAN-bus wire to instrument cluster		Check matching resistor of CAN-bus → CAN-bus, checking
19458 P3002
Kick down switch F8
	Implausible signal	G79 inoperative	Automatic transmission shift points inaccurate	Check Throttle Position Sensor G79 → 20 - FUEL SUPPLY

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
19459 P3003
Low heat output relay J359
	Short to positive (B+)	Wiring open circuit Short to positive (B+) Low heat output relay J359 inoperative	Engine preheating not functioning	Check J359 → Function 03: Output Diagnostic Test Mode (DTM) , Performing Output Diagnostic Test Mode
19461 P3005
High heat output relay J360
	Short to positive (B+)	Wiring open circuit Short to positive (B+) High heat output relay J360 inoperative	Engine preheating not functioning	Check J360 → Performing Output Diagnostic Test Mode , Performing Output Diagnostic Test Mode

DTC VAG1551 display		Possible causes	Possible effects	Corrective action
19560 P3104
Intake manifold flap change-over valve N239
	Short to positive (B+)	Short to positive (B+)	Harder engine stop jolts	Check N239 → Intake Manifold Flap Change-over Valve N239 , checking
19561 P3105
Intake manifold flap change-over valve N239
	Open circuit/short to ground	Wiring open circuit Intake manifold changeover valve inoperative	Harder engine stop jolts	Check N239 → Intake Manifold Flap Change-over Valve N239 , checking