Circuit/System Verification
WARNING: This page is about a different car, the 2017 GMC Yukon XL, 2017 GMC Yukon, 2017 Chevrolet Tahoe, 2017 Chevrolet Suburban 3500 HD, and 2017 Chevrolet Suburban. However, it is still accessible from the selected car via links, so may be relevant.
- Verify the transmission fluid level and condition is correct. Refer to Transmission Fluid Level and Condition Check .
- If the transmission fluid level and condition is not correct
Repair as necessary.
- If the transmission fluid level and condition is correct
- If the transmission fluid level and condition is not correct
- Operate the vehicle until normal engine temperature is reached.
- Verify with a scan tool the ECT Sensor parameter is less than 125°C (257°F).
- If greater than 125°C (257°F)
Refer to Symptoms - Engine Cooling .
- If less than 125°C (257°F)
- If greater than 125°C (257°F)
- Verify the scan tool Transmission Control Module Temperature is less than 142°C (287°F).
- If greater than 142°C (287°F)
Inspect the transmission fluid lines for being misrouted, kinked, or damage. Repair or replace as necessary. If the transmission fluid lines are OK, replace the Q8 Control Solenoid Valve Assembly.
- If less than 142°C (287°F)
- If greater than 142°C (287°F)
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observe from the Freeze Frame/Failure Records data.
- Verify the DTC does not set.
- If the DTC sets
Replace the Q8 Control Solenoid Valve Assembly.
- If the DTC does not set
- If the DTC sets
- All OK.