Test sequence

Ensure that sensor is correctly installed and firmly seated.
Disconnect connector to engine speed sensor. See COMPONENT LOCATIONS, OVERVIEW .

Fig 1: Identifying Engine Speed (RPM) Sensor Connector Terminals
Courtesy of AUDI OF AMERICA, INC.
Connect multimeter between terminals 2 and 3 to measure resistance.
- Specified value: 730 to 1000 Ω

NOTE: The resistance value of the engine speed sensor is associated with a temperature of 20 °C. The resistance increases if the temperature increases.

If specified value is not obtained:

Replace engine speed sensor.

If specified value is obtained:

Fig 2: Identifying Engine Speed (RPM) Sensor Connector Terminals

Courtesy of AUDI OF AMERICA, INC.

Connect multimeter between terminals 2 and 1 (screen) and 3 and 1 (screen) to measure resistance.
- Specified value: each case INFINITY Ω(no continuity)

If specified value is not obtained:

Replace engine speed sensor.

If specified value is obtained:

Connect test box VAG1598/31 to wiring harness for engine control module; do not connect engine control module. See WIRING AND COMPONENT CHECK WITH TEST BOX VAG1598/31 .

Fig 3: Identifying Engine Speed (RPM) Sensor Harness Connector Terminals
Courtesy of AUDI OF AMERICA, INC.

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

ENGINE SPEED (RPM) SENSOR CIRCUIT TEST: OPENS/SHORTS

Connector terminal	Test box VAG1598/31 Socket
1 (screening)	108
2 (ground)	90
3 (signal)	82

Repair any open/short circuit as necessary.

If no wiring malfunction is detected:

Replace engine control module. See ENGINE CONTROL MODULE (ECM), REPLACING .