Turbo Boost Sensor: Testing and Inspection
Charge Air Pressure Sensor G31, Checking
Special tools, testers and auxiliary items required
- Multimeter V.A.G 1526 or equivalent.
- Test Box 105 Pin VAG1598/42.
- Adapter Lead Vag1598/39 VAG1598/39.
- Adapter cable V.A.G 1598/39-1.
NOTE: Use only gold-plated terminals when servicing terminals in harness connector of Charge Air Pressure Sensor G31.
Test requirements
- Fuses for the Engine Control Module (ECM) J623 OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- On vehicles with automatic transmission, selector lever in position "P" or "N".
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Ignition switched off.
Test sequence
- Remove engine cover - arrows -.
- Disconnect the electrical harness connector - 2 - from the Charge Air Pressure Sensor G31.
- Start engine and let it run at idle.
- Using the Multimeter V.A.G 1526 A or equivalent, check the Charge Air Pressure Sensor G31 electrical connector terminals 1+3 for voltage.
Specified value: min. 4.5 V
- Switch ignition off.
If the specification is not obtained:
- Connect the test box 1598/42 to the wiring harness of the Engine Control Module (ECM) J623.
- Using the Test Box 105 Pin VAG1598/42 and Multimeter V.A.G 1526 A or equivalent, check the following wiring connection for an open circuit.
Terminal Test box socket
1 53
3 19
4 38
Specified resistance 1.5 Ohms max.
If the specification is not obtained:
- Check the wiring for a short circuit to Battery positive (+) or an open circuit.
- If necessary, repair the wiring connection.
If no malfunctions are found in the wiring:
- Replace Charge Air Pressure Sensor G31.
Final procedures
After the repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory.
2. If necessary, erase the DTC memory.
3. If the DTC memory was erased, generate readiness code.
- End diagnosis and switch the ignition off.