With Manufacturer's Scan Tool

Engine Speed (RPM) Sensor -G28-, Checking

The engine speed (RPM) sensor -G28- is a speed and reference mark sender. The engine will not start if there is no speed signal. If the speed signal fails when the engine is running, it will cause the engine to stall immediately.

Special tools and equipment
- V.A.G1551 scan tool or V.A.G1552 mobile scan tool with V.A.G1551/3B cable
- V.A.G1598/31 test box
- V.A.G1526 or Fluke 83 multimeter.
- V.A.G1594 adapter set
- Wiring diagram

Test sequence







- Separate gray 3-pin connector -1- to engine speed sensor.







- Measure sensor resistance between contacts 2 + 3 of connector to sensor.
Specification: 730 to 1000 Ohms
- Check sensor for short between contacts 1 + 2 as well as 1 + 3.
Specification: Infinite Ohms

If the specifications are not obtained:
- Replace engine speed (RPM) sensor -G28-.
- Check DTC Memory, if necessary, repair any malfunctions and then Erase DTC Memory.
- Read readiness code. If DTC memory has been erased or engine control module was disconnected from permanent positive, readiness code must be generated again.
Monitors, Trips, Drive Cycles and Readiness Codes
Monitors, Trips, Drive Cycles and Readiness Codes

If no sensor malfunction is detected:







- Connect V.A.G1598/31 test box to control module wiring harness. The engine control module remains disconnected.







- Check wiring between test box and 3-pin connector for open circuit using wiring diagram.
Contact 1 + socket 108
Contact 2 + socket 90
Contact 3 + socket 82
Wire resistance: Max. 1.5 Ohms
- Check wires for short to one another.

If no wiring malfunction is detected:
- Remove sensor and check sensor wheel for secure fit, damage and run-out.

NOTE: There is a larger gap on the sensor wheel. This gap is the reference mark and does not mean that the sensor wheel is damaged.

If no malfunction is detected on sensor wheel:
- Replace engine control module.