No Vehicle Speed Signal (OBD II)

Name of Code:
35 ($23) - No Vehicle Speed Signal

When Monitored:
Continuously with the key on

Set Condition:
This code is set it no vehicle speed signal is received from the CAB (Controller Antilock Brakes) Module for more when 15 seconds for two consecutive trips.

Theory of Operation:
The PCM receives the VSS (Vehicle Speed Signal) from the CAB module. The CAB nodule receives the input from the wheel speed sensors and converts it into a 8000 pulse per mile signal This signal is hen converted to vehicle speed by the PCM. The VSS signal circuit is hardwired from the CAB to he PCM, it is not a bussed message. The PCM broadcasts the Vehicle Speed on the CCD bus for other modules to use.

Possible Causes:
- Open or shorted VSS signal circuit between the CAB and PCM.
- CAB system problems
- Defective PCM.