Some 2025-2026 Equinox and Terrain models equipped with the VT40 transmission (RPO MRQ) may have a no start condition with DTCs P27EC (Transmission Range Control Valve Position Sensor Circuit Performance) and P2797 (Automatic Transmission Electric/Auxiliary Fluid Pump Performance) set in the Transmission Control Module (TCM).
These conditions may be caused by a poor ground connection at G111, G112 and/or G113.
- G111 is located in the left side of the engine compartment, attached to the frame rail.
- G112 is located at the left side of the engine, attached to the top of the transmission.
- G113 is located in the engine compartment, attached is the left side of the cylinder head. (Fig. 3)
Fig. 3
The transmission auxiliary pump (Fig. 4) and wiring harness also may need to be replaced. The electric auxiliary fluid pump is used to keep hydraulic circuits primed during an automatic stop/start event.
Fig. 4
TIP: If the vehicle ignition is cycled, transmission shifting will be disabled and the vehicle will need to be towed. The vehicle may not move until the DTCs are cleared, even if the data shows the vehicle in Park.
Begin diagnosis by verifying the transmission fluid level. The transmission fluid level must be checked when the transmission fluid temperature is between 140–176°F (60–80°C).
Next, verify torque and test G111, G112 and G113 for resistance.
If voltage drop is greater than 0.5 volts, remove the ground from the chassis and inspect for corrosion or paint, or for any damaged threads. If there are not any issues, replace the ground cable assembly and reevaluate the condition.
If voltage drop is less than 0.5 volts, replace the transmission auxiliary pump and wiring harness. Refer to Automatic Transmission Fluid Pump Removal and Automatic Transmission Fluid Pump Installation in the appropriate Service Information.
Refer to Bulletin #25-NA-271 for additional details, including parts information.
– Thanks to Rob Smith
