Engine Speed (RPM) Sensor -G28- Checking

Engine Speed (RPM) Sensor -G28- Checking

Special tools and equipment







- VAG1526A
- VAG1594A
- VAG1598/31


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







- Disconnect harness connector for engine speed (RPM) sensor -G28- (item no. 3) in engine compartment.


NOTE: Coolant reservoir screws must be removed and coolant reservoir must be placed to side in order to access the harness connector The coolant hoses can remain connected.







- Connect multimeter between terminal 1 and 2 for resistance measurement.
- Specification: 730 to 1000


NOTE: Resistance value of the engine speed (RPM) sensor is based on a temperature of 20 °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 1 and 3 (shielding) and to terminals 2 and 3 (shielding) for resistance measurement.
- Specification: Infinity each (no continuity)

If specified value is not obtained:
- Replace engine speed (RPM) sensor.

If specified value is obtained:
- Connect VAG1598/31 test box at wiring harness to Engine Control Module (ECM), do not connect ECM [1][2]Scan Tool Connecting and Initial Checks







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

Harness connector VAG1598/31 test box
Terminal Socket
1 (signal) 82
2 (Ground -GND-) 90
3 (shielding) 108

- Repair open circuit or short circuit if necessary.

If no malfunctions are found in wires:
- Replace Engine Control Module (ECM).