Engine Speed (RPM) Sensor -G28-, Testing

Engine Speed (RPM) Sensor -G28-, Testing







Special tools and equipment
- VAG 1526 A
- VAG1594 A
- VAG 1598/31

NOTE: The Engine speed sensor is a combined speed sender and reference mark sender. Without a signal from the -G28- the engine cannot be started. If the signal from the -G28- fails while the engine is running, the engine will cut out immediately.

Test sequence
- Before carrying out the test, make sure that the sender is correctly installed and firmly seated.







- Unplug connector for Engine speed sensor -1- (color coding: grey connector).







- Connect multimeter (resistance measurement range) between contacts 2 and 3.
- Specification: 730 to 1000 Ohms

NOTE: The resistance value for the Engine speed sensor is based on a temperature of 20 degrees C. As the temperature rises, the resistance value increases.

If the specification is not attained:
- Fit a new Engine speed sensor.

If the specification is obtained:







- Connect multimeter (resistance test range) to contacts 2 and 1 (screening) and to contacts 3 and 1 (screening).
- Specification: Infinity Ohms (no continuity)

If the specification is not attained:
- Install a new Engine speed sensor.

If the specification is obtained:
- Connect test box VAG 1598/31 to wiring harness for engine control module. Do not connect to the engine control module itself. Scan Tool Testing and Procedures







- Test for open circuit and short to positive or Ground in the following wiring connections:

Connector Contact Test box VAG 1598/31 Socket
1 (screening) 108
2 (Ground) 90
3 (signal) 82

- Correct any open/short circuit as necessary.

If no malfunction is detected:
- Install a new engine control module.