Circuit/System 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 ON, engine OFF, verify with a scan tool the TFP Switch 1, TFP Switch 2, and TFP Switch 3 parameters are High.
- If TFP Switch 1, TFP Switch 2, and TFP Switch 3 parameters are the specified value, refer to Control Valve Body Assembly Disassemble and Control Valve Body Cleaning and Inspection . If valve body inspection is normal, replace the shift solenoid indicated by the DTC, refer to Control Valve Solenoid Replacement (SS1, SS2, SS3, TCC, and MAIN MOD) or Control Valve Solenoid Replacement (PCS1 and PCS2) .
- Ignition OFF, disconnect the X175 harness connector at the transmission.
- Ignition ON, engine OFF, verify with a scan tool the TFP Switch 1, TFP Switch 2, and TFP Switch 3 parameters are High.
- If not the specified value, test the affected pressure switch signal circuit for a short to ground. If circuits tests normal, replace the TCM.
- Remove the transmission oil pan. Refer to Oil Pan Replacement .
- Test the transmission internal Pressure Switch 1, 2, and 3 signal circuits for a short to ground.
- If the circuits test normal, replace the PSM. Refer to Pressure Switch Manifold Replacement .
NOTE:
You must perform the Circuit/System Testing first.