Component Testing
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, transmission in Park or Neutral, disconnect the transmission 16-way connector and the manual shift shaft position switch connector from the control solenoid (w/body and TCM) valve assembly.
- Test for infinite resistance between the control solenoid (w/body and TCM) valve assembly 16-way connector pin 3 and the manual shift shaft position switch connector pin F on the control solenoid (w/body and TCM) valve assembly side with the switch in the Open position - Reverse or Drive.
- If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the control solenoid (w/body and TCM) valve assembly.
- Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection before replacing the control solenoid (w/body and TCM) valve assembly.
- Test for infinite resistance between the IMS connector pin F and the IMS case ground with the switch in the Open position - Reverse or Drive.
- If not the specified value, replace the IMS.
IMPORTANT:
The manual shift shaft position switch contacts are made of stainless steel. This material makes it difficult to obtain stable ohm readings to determine the switch resistance. Therefore, the diagnosis should eliminate all other components first, leaving the switch as the last possible cause.