With Generic Scan Tool

Charge Air Pressure Sensor -G31-, Checking

Recommended special tools and equipment







- VAG1526A hand multimeter
- VAG1594A connector test kit
- VAG1598/31 test box

Work procedure







- Disconnect connector (arrow) at charge air pressure sensor.

Checking voltage supply







- Connect multimeter between terminal 1 and 3 of harness connector for voltage measurement.
- Switch ignition on.
- Specified value: about 5 V

- Switch ignition off.

If specified value is not obtained:
- Connect test box to wiring harness of Engine Control Module (ECM); ECM is not connected. Test Box, Connecting For Wiring Test







- Check the following wire connections for open circuit and short circuit to Ground (GND) and B+:

Harness connector Terminal Test box Socket
1 108
3 98

- Repair open circuit in wiring or short circuit if necessary.

If specified value is obtained:

Checking signal wire
- Connect harness connector at charge air pressure sensor.
- Connect multimeter to socket 101 and socket 108 of test box for voltage measurement.
- Start engine and let run at idle.
- Specified value: about 1.90 V

- Bring engine to RPM by depressing pedal suddenly.
- Specified value: 2.00 ... 3.00 V

If specified values are not obtained:







- Check the following wire connection for open circuit and short circuit to Ground (GND) and B+:

Harness connector Terminal Test box Socket
4 101

- Specified value: Wire resistance max 1.5 Ohm

- Also check the wire for short circuit to B+ and Ground (GND).
- Specified value: Infinite Ohm (no continuity)

- If necessary, repair wire connection.

If no malfunctions are found in wire:
- Replace the Charge Air Pressure Sensor -G31-.

Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1 - Check DTC memory, see "Mode 3: Check DTC memory". Diagnostic Mode 3: Check DTC Memory
2 - If necessary, erase DTC memory, see "Mode 4: Reset/erase diagnostic data". Diagnostic Mode 4: Reset/Erase Diagnostic Data
3 - Generate readiness code. Readiness Code, Generating

- End diagnosis and switch ignition off.