Turbo Boost Sensor: Testing and Inspection

Charge air pressure sensor, checking
Test requirement





^ On Board Diagnostic (OBD) recognized a malfunction and stored a DTC in DTC memory.

Special tools and equipment
^ VAG1526A multimeter
^ VAG1594A connector test kit
^ VAG1598/31 test box
^ Wiring diagram

Checking voltage supply and wiring to control module





- Switch ignition off.
- Disconnect 4-pin connector -2- from charge air pressure sensor (G31) -2-.





- Use adapter cables from V.A.G 1594 to connect multimeter to terminals 1 + 3 of connector for voltage measurement.
- Switch ignition on.
Specification: at least 4.5 V
- Switch ignition off.
If specified value is not obtained:





- Connect VAG1598/31 test box to control module wiring harness. Engine Control Module (ECM) is not connected.





- Check for open circuits in wires between test box and connector according to wiring diagram.
Terminal 1 + socket 108
Terminal 2 + socket 98
Terminal 4 + socket 101
Wire resistance: maximum: 1.5 Ohms
- Check wires for shorts among one another.
If no malfunctions are found in the wires and there was voltage between terminals 1 + 3:
- Check function
If no errors are found in wires and there was no voltage between terminals 1 + 3:
- Replace Engine Control Module (ECM):
Refer to Computers and Control Systems.

Checking function





- Connect VAG1598/31 test box to control module wiring harness and to control module.
- Re-connect connector at charge air pressure sensor -G31-.
- Connect multimeter to socket 101 and socket 108 for voltage measurement.
- Start engine and measure voltage.
Specification: 1.80 to 2.00 volts
- Bring engine to RPM by depressing accelerator pedal suddenly.
Specification: 2.00 to 3.00 volts
If specified values are not obtained:
- Replace the charge air pressure sensor -G31-.