P0608
DTC P0608
CIRCUIT DESCRIPTION
The vehicle speed signal circuit is an input to the throttle actuator control (TAC) module from the powertrain control module (PCM). The PCM provides a constant voltage signal on the vehicle speed signal circuit. The PCM creates the vehicle speed signal by internally pulsing the vehicle speed signal to ground. The TAC module uses the vehicle speed signal from the PCM, in order to determine the vehicle speed. The TAC module then sends a universal asynchronous receiver transmitter (UART) serial data message to the PCM indicating the vehicle speed that the TAC module has detected.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0608 Vehicle Speed Output Circuit
CONDITIONS FOR RUNNING THE DTC
- The ignition is ON.
- There are no vehicle speed sensor (VSS) DTCs present in the PCM.
- The ignition voltage is between 9-16 volts.
CONDITIONS FOR SETTING THE DTC
- The PCM detects that the commanded state of the driver and the actual state of the control circuit do not match.
- The condition must be present for a minimum of 5 seconds.
ACTION TAKEN WHEN THE DTC SETS
- The Cruise Control System is disabled.
- The PCM stores a DTC P0608 in memory.
- The PCM records the operating conditions at the time the DTC sets. The PCM displays the failure information in the Failure Records on the scan tool.
CONDITIONS FOR CLEARING THE DTC
- The history DTC clears after 40 malfunction-free warm-up cycles.
- The DTC becomes history when the conditions for setting the DTC are no longer present.
- The PCM receives the clear code command from the scan tool.
DIAGNOSTIC AIDS
For intermittent diagnosis.
TEST
