Governor Pressure Not Equal to Target 15-20 Psi (OBD II)

Name of Code:
141 ($SD) - Governor Pressure Not Equal to Target @ 20-25 PSI

When Monitored:
Continuously with the key on and engine running.

Set Condition:
A fault condition is identified it the output of the governor pressure sensor is below 15 PSI or above 30 PSI when the requested pressure is between 20 and 25 PSI for 2.2 seconds. The code is set when after five consecutive bad 2.2 second tests.

Theory of Operation:
The governor pressure control system is used to regulate governor pressure. Governor pressure is raised or lowered by changing the duty cycle of the governor pressure solenoid. This is done by the PCM and is based on input from the Output Speed Sensor. The governor pressure solenoid is normally open, therefore 0% duty cycle provides full governor pressure and 100% duty cycle would provide 0 PSI governor pressure. The governor pressure sensor provides a voltage signal to the PCM. The PCM compares this to the target governor pressure and makes changes accordingly.

Transmission effects:
Governor pressure solenoid duty cycle is set to minimum. This results in 3rd gear launch. 4th gear (OD) and TCC operation remain unchanged. The MIL is illuminated.

Possible Causes:
- Corroded, damaged, pushed out, miswired, or disconnected connector(s)
- Governor Pressure Sensor allure
- Governor Pressure Solenoid failure
- Internal controller failure (PCM)