Manufacturer's Scan Tool

Engine Speed Sensor, Checking

Special tools, testers and auxiliary items required

• Multimeter (V.A.G 1526 A)

• Connector test kit (V.A.G 1594 A)

• Test box (VAG1598/31)

Component location => [ (Item 6) ] Locations

• The engine speed (RPM) sensor is a combined speed sensor and reference mark sensor. The engine cannot be started without a signal from the Engine speed (RPM) sensor (G28). If the signal from the Engine speed (RPM) sensor (G28) fails while the engine is running, the engine will cut out immediately.

Work sequence

- Before performing test, make sure that sensor is correctly installed and firmly seated.

- Disconnect Engine speed (RPM) sensor connector ( G28)- 3 -.

• To gain access to the connector, remove coolant expansion tank bolt (arrow) and move expansion tank to the side. Fuel hoses remain connected.

- Connect multimeter between terminals 2 and 3 to measure resistance.

• Specified value: 730...1000 ohms

• The resistance value of the Engine speed (RPM) sensor (G28) is associated with a temperature of 20° C. The resistance increases if the temperature increases.

If specified value is not obtained:

- Install new Engine speed (RPM) sensor (G28).

If specified value is obtained:

- Connect multimeter between terminals 2 and 1 -screen- and 3 and 1 -screen- to measure resistance.

• Specified value: each case infinite ohms (no continuity)

If specified value is not obtained:

- Install a new Engine speed (RPM) sensor (G28).

If specified value is obtained:

- Connect test box (VAG1598/31) to wiring harness for ECM; do not connect ECM => [ Electrical Testing, with Test Box VAG 1598/31 ] Electrical Testing, With Test Box VAG 1598/31.

- Check for open circuit, short to positive, or short to ground in following wiring connections:

- Repair any open/short circuit as necessary.

If no wiring problems are found:

- Replace ECM => [ Engine Control Module without Metal Anti-Theft Housing, Replacing ] Engine Control Module Without Metal Anti-Theft Housing, Replacing.