Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble talking to one of the parts that helps change gears. It's like when your walkie-talkie keeps cutting out, and you can't hear your friend clearly.
The P078E code is triggered when the transmission control module detects an intermittent issue with the shift timing solenoid B, which is responsible for controlling the timing of gear shifts.
The P078E code indicates that the transmission control module (TCM) has detected an intermittent fault in the electrical circuit of shift timing solenoid B. This solenoid is part of the transmission system and helps regulate hydraulic pressure to facilitate smooth gear changes. An intermittent fault suggests that the problem is not constant, making it more challenging to diagnose.
• Erratic or harsh shifting
• Transmission slipping
• Illuminated check engine light
• Faulty shift timing solenoid B
• Wiring issues such as damaged or corroded connectors
• Malfunctioning transmission control module (TCM)
Transmission Control Module (TCM): A computer that controls the transmission functions.
Solenoid: An electromechanical device that controls the flow of fluid in the transmission.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the shift timing solenoid B for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty shift timing solenoid B.
• Update or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid changes
• Routine inspection of wiring and connectors
• Avoiding aggressive driving
Transmission Issue
• Avoid driving aggressively until the issue is resolved.
• Have the vehicle inspected by a professional mechanic.
Check with your vehicle manufacturer for warranty coverage on transmission components.
The P078E code has been reported in various models, often linked to wiring issues or solenoid failures.
Moderate – While the vehicle may still be drivable, unresolved transmission issues can lead to more severe problems.
Driving with transmission issues can lead to unsafe driving conditions. It is recommended to address the problem promptly.
• Vehicle at operating temperature
• Transmission in drive mode
The shift timing solenoid B is located inside the transmission, typically accessible by removing the transmission pan.
Q: Can I drive with a P078E code?
A: It's possible to drive with this code, but it's not recommended as it can lead to further transmission damage.
Q: How do I reset the P078E code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, it should not return.
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