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 has detected a problem with the electrical circuit that controls one of the pressure control parts in the transmission. It's like when a light switch doesn't work because the wires are loose.
The code P0966 indicates that the transmission control module (TCM) has detected a low voltage or open circuit condition in the pressure control solenoid B control circuit.
Pressure control solenoids are used in automatic transmissions to regulate hydraulic pressure. The solenoid B is responsible for controlling the pressure applied to specific transmission components. A low circuit condition suggests a problem with the electrical signal reaching the solenoid, which can affect transmission performance.
• Harsh or erratic shifting
• Transmission slipping
• Illuminated check engine light
• Faulty pressure control solenoid B
• Wiring issues such as short or open circuits
• Faulty transmission control module (TCM)
Solenoid: An electromechanical device that controls the flow of fluid.
TCM: Transmission Control Module, the computer that controls transmission functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the pressure control solenoid B for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty pressure control solenoid B.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Honda Accord
• Toyota Camry
• Ford Focus
• Regularly inspect and maintain transmission fluid levels.
• Ensure wiring and connectors are free from corrosion.
• Perform routine transmission maintenance.
Transmission Control Issue
• Avoid driving aggressively until the issue is resolved.
• Have the vehicle inspected by a professional mechanic.
• Consider regular transmission service to prevent future issues.
Check with your vehicle manufacturer for specific warranty coverage related to transmission components.
This code has been associated with vehicles experiencing transmission performance issues due to electrical problems in the solenoid circuits.
Moderate – It's important to address this issue to prevent potential transmission damage.
Driving with transmission issues can lead to safety hazards. It is advised to address the problem promptly.
• Vehicle must be at operating temperature.
• Ensure the battery is fully charged.
The pressure control solenoid B is located inside the transmission, usually accessible by removing the transmission pan.
Q: Can I drive with a P0966 code?
A: It's not recommended to drive for extended periods with this code, as it can lead to transmission damage.
Q: How can I prevent this code from appearing again?
A: Regular maintenance and inspection of the transmission system can help prevent this code.
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