With Generic Scan Tool

Engine Speed (RPM) Sensor -G28-, Checking







Recommended special tools and equipment
- V.A.G1526A hand multimeter
- V.A.G1594A connector test kit
- V.A.G1598/31 test box

NOTE: The engine speed (RPM) sensor detects RPM and reference marks. The engine cannot be started without a signal from the engine speed (RPM) sensor -G28-. If the engine speed (RPM) sensor -G28- signal fails while the engine is running, the engine will stop immediately.

Test requirement:
- Ignition switched off.

Procedure
- Before performing test, check sensor for proper installation and proper fitting.







- Disconnect harness connector at Engine Speed (RPM) Sensor -G28- (item 3).

NOTE:







Coolant reservoir screw (arrow) must be removed and coolant reservoir must be placed to the side in order to access harness connector. The coolant hoses remain connected.

Checking internal resistance







- Connect multimeter between terminal 2 and 3 for resistance measurement.

Specified value: 730 to 1000 Ohms

NOTE: Resistance value of the engine speed (RPM) sensor is based on a temperature of 20 degrees C. Resistance increases as temperature increases.

If specified value is not obtained:
- Replace Engine Speed (RPM) sensor.

If specified value is obtained:







- Connect multimeter to terminals 2 and 1 (shielding) and to terminals 3 and 1 (shielding) for resistance measurement.

Specified value: each infinite Ohms (no continuity)

If specified value is not obtained:
- Replace Engine Speed (RPM) sensor.

If specified value is obtained:

Checking wire connections
- Connect test box to wiring harness of Engine Control Module (ECM). ECM is not connected. Test Box, Connecting For Wiring and Component Test







- Check the following wire connections for open circuit according to wiring diagram:

Harness connector Terminal Test box Socket
1 (shielding) 180
2 (Ground-GND-) 90
3 (signal) 82

Specified value: Wire resistance max 1.5 Ohms

- Also check wires for short circuit to each other as well as to B+ and Ground (GND).

Specified value: Infinite Ohms (no continuity)

- If necessary, repair wire connection.

If no malfunctions are detected:
- Replace Engine Control Module (ECM).

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

- End diagnosis and switch ignition off.