how to fix GMC Sierra T1XX (2019-Present) transmission code P0750

Learn how to diagnose and fix P0750 transmission code in GMC Sierra T1XX. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, torque wrench, transmission fluid pump, safety glasses, gloves.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Lift the vehicle using a jack and secure it with jack stands for safety.

2. Remove the Transmission Pan

• Sub-steps:
  1. Place a drain pan under the transmission pan to catch fluid.
  2. Remove the bolts securing the transmission pan using a socket set.
  3. Carefully lower the pan and drain the fluid completely.

3. Remove the Shift Solenoid A

• Sub-steps:
  1. Locate the shift solenoid A within the transmission assembly.
  2. Disconnect the electrical connector from the solenoid.
  3. Remove the retaining bolts of the solenoid using the socket set.
  4. Carefully pull the solenoid out of its housing.

4. Install New Shift Solenoid A

• Sub-steps:
  1. Compare the new solenoid with the old one to ensure correct part.
  2. Insert the new solenoid into the designated slot and secure it with the retaining bolts.
  3. Reconnect the electrical connector to the solenoid.

5. Reinstall the Transmission Pan

• Sub-steps:
  1. Clean the mating surface of the transmission and the pan.
  2. Apply a new gasket or sealant as required.
  3. Position the pan back onto the transmission and tighten the bolts to the manufacturer’s specified torque.
  4. Refill the transmission with the appropriate type and amount of transmission fluid using the fluid pump.

6. Reconnect Battery and Test

• Reconnect the negative battery terminal.
• Start the engine and allow it to reach operating temperature. Check for leaks around the transmission pan.
• Test drive the vehicle to ensure proper shifting and verify that the check engine light does not reappear.