Circuit/System Testing
WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Perform the Line Pressure Check
. Verify the transmission line pressures are within the specified ranges.
- If not within the specified ranges, refer to Fluid Pressure High or Low .
- Ignition OFF, remove the Q8 control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement .
- Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test
. Test all solenoids on the Q8 control solenoid valve assembly. A pressure change should occur for each solenoid valve.
- If the Q8 control solenoid valve assembly does not pass the performance test, replace the Q8 control solenoid valve assembly.
- Listed in the chart below are conditions for each component that could set DTC P0756. Carefully inspect each component for that condition. Repair or replace as necessary.
| DTC | Component | Condition |
|---|---|---|
| P0756 | Lower Control Valve Body (351) | Clutch select valve 3 stuck off - debris, sediment, binding or scored bore |
| P0756 | Lower Control Valve Body (351) | Bore Plug - Clutch Select Valve 3 leaking, undersized bore plug, damaged |
| P0756 | Lower Control Valve Body (351) |
|
| P0756 | Q8 Control Solenoid Valve Assembly (314) | Shift Solenoid (SS) 2:
|
| P0756 | 1-2-3-4 and 3-5-R Clutch Housing Assembly (51) | 1-2-3-4 clutch backing plate retaining ring not seated, causing the piston to over travel and cut the 1-2-3-4 clutch piston seal |
| P0756 | Fluid Pump Cover Assembly | Fluid pump cover vanes and fluid pump rotor broken |
| P0756 | Low Clutch Sprag Assembly | Broken or incapable of holding torque |
| P0756 | Pump Seal | Seal is cut, torn causing a leak due to pump speed and capacity |