The P0788 trouble code indicates a high voltage condition in the Shift Timing Solenoid A circuit of the transmission. Here’s what you should know:
P0788 Shift Timing Solenoid A High
Code symptoms P0788.
1. Check Engine Light (CEL) illuminated on the dashboard.
2. Harsh or delayed shifting between gears.
3. Failure to shift into certain gears.
4. Decreased fuel efficiency.
5. Vehicle may go into limp mode to prevent further damage.
This code is common in brands such as:: Chevrolet, Renault, Ford, Toyota, Nissan, Mercedes Benz, Honda.
Causes of the code P0788.
1. High transmission fluid level or dirty or contaminated fluid.
2. Malfunctioning Shift Timing Solenoid A.
3. Faulty transmission control module (TCM).
4. Electrical issues, such as a short circuit or open circuit in the wiring harness or connectors related to the Shift Timing Solenoid A.
5. A malfunctioning transmission control module (TCM).
Code Solutions P0788.
1. Begin by using a scan tool to retrieve freeze frame data and any other stored codes. This information can provide insight into when and how the malfunction occurred.
2. Check the transmission fluid level and condition. If the fluid level is too high, drain it to the proper level. If the fluid is dirty or contaminated, consider performing a transmission fluid flush and refill.
3. Perform a visual inspection of the transmission wiring harness and connectors related to the Shift Timing Solenoid A for any signs of damage, corrosion, or loose connections. Repair or replace any damaged wiring or connectors as needed.
4. Use the scan tool to monitor live data from the transmission control module (TCM) while test driving the vehicle. Pay attention to data related to the Shift Timing Solenoid A voltage. Any abnormalities can help pinpoint the issue.
5. If no issues are found during the above steps, consider performing an electrical test of the Shift Timing Solenoid A circuit using a multimeter or other diagnostic tools to verify voltage and continuity.
6. If necessary, test the Shift Timing Solenoid A and other transmission components using a multimeter or other diagnostic tools to ensure they are functioning properly.
7. If all else fails, consult the vehicle’s service manual or seek assistance from a qualified mechanic or transmission specialist for further diagnosis and repair.