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 computer in your car has detected a problem with one of the parts that helps your car change gears. It's like a switch is stuck in the 'on' position when it shouldn't be.
The P0977 code indicates that the transmission control module (TCM) has detected an unusually high voltage in the shift solenoid B control circuit.
Shift solenoids are responsible for controlling the flow of transmission fluid in the valve body, which in turn controls the shifting of gears in an automatic transmission. The P0977 code is set when the TCM detects a high electrical condition in the circuit that controls shift solenoid B, suggesting a possible short to voltage or a malfunctioning solenoid.
• Transmission may not shift properly
• Check Engine Light is on
• Poor fuel economy
• Faulty shift solenoid B
• Wiring issues such as short to voltage
• Faulty transmission control module (TCM)
Shift Solenoid: An electromechanical valve that controls the flow of transmission fluid.
Transmission Control Module (TCM): A computer that controls the operation of an automatic transmission.
• Use an OBD-II scanner to verify the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the shift solenoid B for proper operation.
• Replace or repair damaged wiring or connectors.
• Replace the shift solenoid B if faulty.
• Replace or reprogram the TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Honda Accord
• Toyota Camry
• Ford F-150
• Regular transmission fluid changes
• Routine inspection of wiring and connectors
• Avoiding aggressive driving habits
Transmission Control Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional mechanic.
Check with your vehicle manufacturer; transmission components may be covered under powertrain warranty.
This code has been associated with transmission issues in vehicles with high mileage or poor maintenance.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with a malfunctioning transmission can be unsafe. Address the issue as soon as possible.
• Vehicle at operating temperature
• Transmission in drive mode
The shift solenoid B is located inside the transmission, attached to the valve body.
Q: Can I drive with a P0977 code?
A: It's not recommended to drive with this code for an extended period, as it may cause further transmission damage.
Q: How do I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scanner to clear the code after repairs are completed.
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