Vehicle Speed Sensor: Testing and Inspection

Speed Signal, Checking

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram

Test requirements
- The respective fuses of Engine Control Module (ECM) -J623- must be OK.
- Battery voltage must be at least 11.5 Volts.
- Speedometer -G21- must be OK.

Test sequence

NOTE: To test speed signal, vehicle must be driven. Doing this requires a second person.

CAUTION:
- Test and measuring equipment must always be secured to the rear seat and operated from there by a second person.
- If test and measuring equipment is operated from the passenger seat, the person seated there could be injured in the event of an accident involving deployment of the passenger-side airbag.

- Connect diagnostic tester Scan Tool Connecting
- Start engine and let run at idle.
- Under address word 33, select "Diagnostic mode 1: Checking measured values."
- Select the measuring value "PID 13: Vehicle speed".
- Perform a road test, and have the 2nd person observe the indication on the display.
- Check specified value of the vehicle speed:

PID Diagnostic text Specified value:
13: Vehicle speed approx. vehicle speed

- End diagnosis and switch ignition off.

If no speed is indicated:
- Check DTC memory.
- Read readiness code. If DTC memory was erased, readiness code must be generated again