Checking The Vehicle Speed Sensor (VSS) Signal

Fig 1: Engine Start Verification

Courtesy of VOLVO CARS CORPORATION

Ignition off
Check the transmission control module (TCM) and speed sensor connectors. Check for contact resistance and oxidation according to CONTACT RESISTANCE AND OXIDATION . Remedy if necessary
Raise the car so that the drive wheels are clear of the ground
Start the engine. Allow the engine to idle
Move the gear selector to position D so that the drive wheels begin to rotate
Read off the transmission speed.
Depress the accelerator pedal (AP) and check that the speed is updated.

NOTE:
Ensure that the wheels are not rotating when the gear selector is moved.

NOTE:
Diagnostic trouble codes (DTCs) may be stored in the ABS system when the rear wheels are stationary and the front wheels rotate. Erase any diagnostic trouble codes (DTCs) stored in the ABS system after fault-tracing.

If the speed is updated, the cause of the fault was probably contact resistance or oxidation in the control module or vehicle speed sensor (VSS) connectors.

Fig 2: Identifying VCT2000 Diagnostic Tool Symbol In VIDA
Courtesy of VOLVO CARS CORPORATION

Was the speed updated?