Test sequence
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.
- Connect Scan Tool VAG1551 ( VAG1552 ) and select engine electronics control unit with the "Address word" 01. When doing this the engine must be running at idling speed. (Connecting Scan Tool and selecting engine electronics control unit → Scan Tool VAG1551 , connecting .)
Indicated on display:
| Rapid data transfer HELP Select function XX |
- Press buttons 0 and 3 for the function "Output Diagnostic Test Mode".
Indicated on display:
| Rapid data transfer Q 03 Final control diagnosis |
- Confirm input with Q button.
Indicated on display:
| Final control diagnosis → Commencement of injection valve -N108 |
- Press the → button.
Indicated on display:
| Final control diagnosis → Exhaust gas recirculation valve -N18 |
- Press the → button.
Indicated on display:
| Final control diagnosis → Conditioner compressor interruption |
A/C compressor switch-off is checked.
A/C compressor must stop within 5 seconds (visual check) then start approx. every 5 seconds and then stop.
If the A/C compressor is not switched off:
- Proceed with function 3: Output DTM, until complete.
- Press buttons 0 and 6 for the function "End output" and confirm entry with the Q button.
- Switch off ignition.
- Remove wiper arms and plenum cover: → 92 WINDSHIELD WIPER & WASHER SYSTEM
- Connect test box VAG1598/31 to control unit wiring harness.
- Check wiring between test box socket 29 and the A/C system for open circuit using wiring diagram. Wire resistance: Max. 1.5 Ω → Electrical Wiring Diagrams, Troubleshooting and Component Locations
- Check DTC memory and, if necessary, repair any malfunctions and then erase → Diagnostic Trouble Code (DTC) memory, checking and erasing .
- Read readiness code → Reading readiness code . If the DTC memory has been erased, the readiness code must be generated again → Readiness code, setting .
- Connect Scan Tool VAG1551 ( VAG1552 ) and select engine electronics control unit with the "Address word" 01. When doing this the engine must be running at idling speed. (Connecting Scan Tool and selecting engine electronics control unit → Scan Tool VAG1551 , connecting .)
Indicated on display:
| Rapid data transfer HELP Select function XX |
- Press buttons 0 and 8 for the function "Read measured value block" and confirm entry with Q button.
Indicated on display:
| Read measured value block Enter display group number XXX |
- Press buttons 0 , 0 and 2 for "Display group number 2" and confirm entry with Q button.
Indicated on display: (1 through 4 = Display fields)
| Read measured value block 2 → 1 2 3 4 |
- Observe display in display field 3, the A/C must not be switched on.
Specification: 0 X 0 (A/C system signal)
| Read measured value block 2 → 1 2 0 1 0 4 |
- Switch on A/C system. Do this, depending on A/C system installed by pressing switch "AC" on a manually controlled A/C system or pressing switch "Auto" on an automatic (Climatronic) A/C system.
- Select lowest temperature and highest blower speed. The A/C compressor must run.
- Observe display in display field 3.
Specification: X X 1 (A/C system signal)
| Read measured value block 2 → 1 2 1 1 1 4 |
- Press → button.
- Press buttons 0 and 6 for the function "End output" and confirm entry with the Q button.
- Switch off ignition.
| Significance when display = 1 | |||
| x | x | x | Engine operating condition |
| 1 | A/C compressor switched on | ||
| 1 | Idling switch closed | ||
| 1 | Increased idling speed because A/C is switched on | ||
If the specification is not obtained:
- Remove wiper arms and plenum cover: → 92 WINDSHIELD WIPER & WASHER SYSTEM
- Connect test box VAG1598/31 to control unit wiring harness.
- Check wiring between test box socket 34 and A/C system for open circuit using wiring diagram. Wire resistance: Max. 1.5 Ω → Electrical Wiring Diagrams, Troubleshooting and Component Locations
If no malfunction can be found in wiring:
- Check function of A/C control unit.
- Check DTC memory and, if necessary, repair any malfunctions and then erase → Diagnostic Trouble Code (DTC) memory, checking and erasing .
- Read the readiness code → Reading readiness code . If the DTC memory has been erased, the readiness code must be generated again → Readiness code, setting .