Output Diagnostic Test Mode (DTM), performing

The Output Diagnostic Test Mode (DTM) actuates the listed components in the following sequence:

1. Fuel Injector, Cyl. 1 (N30)
2. Fuel Injector, Cyl. 2 (N31)
3. Fuel Injector, Cyl. 3 (N32)
4. Fuel Injector, Cyl. 4 (N33)
5. Fuel Injector, Cyl. 5 (N83)
6. Fuel Injector, Cyl. 6 (N84)
7. Idle Air Control valve (N71)
8. Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80)
9. Heated Oxygen Sensor (HO2S) relay (J278)
10. EGR Vacuum Regulator Solenoid Valve (N18), (two-way valve). Only applicable for vehicles equipped with EGR
11. Intake Manifold Change-Over valve (N 156). Ignore display.
12. Secondary Air Injection (AIR) Pump Relay (J299). Only applicable for vehicles equipped with Secondary Air Injection (AIR).
13. Secondary Air Injection (AIR) Solenoid Valve (N112). Only applicable for vehicles equipped with Secondary Air Injection (AIR).

• Throttle Position (TP) Sensor (G69) OK.

• Connect the VAG 1551 Scan Tool (ST) using VAG 1551/3 adapter harness, see VAG 1551 SCAN TOOL, CONNECTING/SELECTING FUNCTION .
• Switch ignition ON.

Operate VAG 1551 Scan Tool (ST) according to information and instructions on the display:

• Press PRINT button.
• Press button -1- for "Rapid data transfer" operating mode.

  Indicated on display

  Fig 1: Identifying VAG 1551 Scan Tool - Rapid Data Transfer Help Display

  
• Press buttons -0- and -1- to enter address word 01 for "Engine Electronics"
• Press -Q- button to confirm input.
• Press --> button.
• Press buttons -0- and -3- for "Output Diagnostic Test Mode" function.

  Indicated on display

  Fig 2: Identifying VAG 1551 Scan Tool - Output Diagnostic Test Mode

  
  NOTE: If anything else appears in the display: VAG 1551 Scan Tool (ST) operating instructions.

To activate Cyl. 1 Fuel Injector (N30):

• Press -Q- button to confirm input.

  Indicated on display

  Fig 3: Identifying VAG 1551 Scan Tool - Cyl. 1 Fuel Injector

  
• Open throttle valve to Wide Open Throttle and close.
  • Cyl. 1 Fuel Injector (N30) must click

For Cyl. 2 - Cyl. 6 Fuel Injectors (N31-N33, N83, N84) in each case:

• Again open throttle valve to Wide Open Throttle and close.

Skipping individual tests:

• Press --> button.

If one or more of the Fuel Injectors does not click:

• Complete Output Diagnostic Test Mode (DTM).
• Switch ignition OFF.
• Carry out additional electrical testing:
  • See ELECTRICAL TEST (STEPS 12 TO 19) ELECTRICAL TESTING WITH (VAG1598 TEST BOX) , test steps 12 through 17
  • Check Fuel Injector actuation (resistance and current), see FUEL INJECTORS, CHECKING

To activate Idle Air Control (IAC) valve (N71):

• Press button.

  Indicated on display

  Fig 4: Identifying VAG 1551 Scan Tool - Idle Air Control (IAC) Valve

  

  The Idle Air Control valve must click, until switching to the next DTM component by pressing the --> button.

  The IAC Valve (N71) must click until switching to the next test in the DTM sequence by pressing the --> button.

• Switch ignition OFF.
• Disconnect harness connector from IAC Valve (N71).
• Connect VAG 1527 LED tester to connector terminals -1- and -2- of using cables from VAG 1594 adapter kit.
• Switch ignition ON.
• Repeat Output Diagnostic Test Mode (DTM) - activate Idle Air Control (IAC) Valve (N71).
  • If LED flashes:

  LED must flash

• Replace Idle Air Control (IAC) Valve (N71).

If LED does NOT flash:

• Switch ignition OFF.
• Reconnect harness connector to Idle Air Control (IAC) Valve (N71).
• Carry out electrical testing, see ELECTRICAL TEST (STEPS 25 TO 27) , test step 27.
  • If necessary, replace Motronic Engine Control Module (ECM) (J220).

To activate Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80):

• Press --> button.

  Indicated on display

  Fig 5: Identifying VAG 1551 Scan Tool - Evaporative Emission (EVAP) Canister Purge Regulator Valve

  
  • The EVAP Canister Purge Regulator Valve (on Air Cleaner Housing) must click until the next test in the DTM sequence is selected by pressing the --> button
• Disconnect hose from EVAP Canister Purge Regulator Valve (hose from EVAP Canister).
• Connect auxiliary hose to valve.
• During Output Diagnostic Test Mode (DTM) blow into auxiliary hose (in direction of throttle housing).
  • Valve solenoid must open and close

If the valve solenoid does not click:

• Disconnect two-pin connector from valve and connect US 1115 LED tester across connector terminals using cables from VW 1594 adapter kit.

• The LED must flash

If YES:

• Replace EVAP Canister Purge Regulator Valve (N80).

If NO:

• Switch ignition OFF.
• Reconnect two-pin connector to EVAP Canister Purge Regulator Valve (N80).
• Carry out electrical testing, see ELECTRICAL TEST (STEPS 12 TO 19) , test step 18.

• If necessary replace Motronic Engine Control Module (J220)

To activate Heated Oxygen Sensor (HO2S) Relay (J278):

• Press --> button.

  Indicated on display

  Fig 6: Identifying VAG 1551 Scan Tool - Heated Oxygen Sensor (HO2S) Relay (J278)

  
  • HO2S Relay (J278) (on auxiliary fuse/relay panel) must click until the next test in the DTM sequence is initiated by pressing the --> button

If Relay (J278) does not click:

• Switch ignition OFF.
• Carry out electrical testing, see ELECTRICAL TEST (STEPS 6 AND 7) , test step 6, or locate and repair short circuit in wiring.

If an open circuit cannot be located:

• Replace Heated Oxygen Sensor (HO2S) Relay or Motronic Engine Control Module (ECM) (J220) as necessary.

To activate EGR Vacuum Regulator Solenoid Valve (N18) two-way valve:

• Press --> button.

  Indicated on display

  Fig 7: Identifying VAG 1551 Scan Tool - EGR Vacuum Regulator Solenoid Valve (N18)

  
  • EGR Vacuum Regulator Solenoid Valve (N18) must click

If the valve does not click:

• Disconnect two-pin connector from valve and connect US 1115 LED tester across connector terminals using cables VW 1594 adapter kit.

If LED flashes:

• Replace EGR Vacuum Regulator Solenoid Valve (N18) two-way valve.

If LED does not flash:

• Carry out electrical testing, see ELECTRICAL TEST (STEPS 31 TO 35) , test steps 33 and 34.
  • If necessary, replace Motronic Engine Control Module (J220)
• Press --> button.

  Indicated on display

  Fig 8: Identifying VAG 1551 Scan Tool - Output Diagnostic Test Mode Display

  
  • Ignore display
• Press button.

To activate Secondary Air Injection (AIR) pump relay (J299):

• Press --> button.

  Indicated on display

  Fig 9: Identifying VAG 1551 Scan Tool - Secondary Air Injection (AIR) Pump Relay (J299)

  

  The Secondary Air Injection (AIR) pump Motor (V101) must run until the next test in the DTM sequence is initiated by pressing the --> button.

If the pump motor does not run:

• Switch ignition OFF.
• Carry out electrical testing, see ELECTRICAL TEST (STEPS 31 TO 35) , test step 35, or locate and repair short circuit in wiring.

If an open circuit cannot be located:

• Replace Secondary Air Injection pump relay (J299) or Motronic Engine Control Module (J220) as necessary.

To activate Secondary Air Injection (AIR) solenoid valve (N112):

• Press --> button.

  Indicated on display

  Fig 10: Identifying VAG 1551 Scan Tool - Output Diagnostic Test Mode Display

  
  • Valve (N112) must click

If the Valve (N112) does not click:

• Switch ignition OFF.
• Carry out electrical testing. See ELECTRICAL TEST (STEPS 31 TO 35) , test step 35, or locate and repair short circuit in wiring.

If an open circuit cannot be located:

• Replace Secondary Air Injection solenoid valve (N112) or Motronic Engine Control Module (J220) as necessary.

If the valve clicks:

• Press --> button.
• Press buttons -0- and -6- to select the "End Output" function
• Press -Q- to confirm input.
• Switch ignition OFF.