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 the part that lets you switch gears manually. It's like when your game controller isn't working right and the buttons don't always do what they're supposed to.
The P0959 code indicates an intermittent problem with the circuit that controls the manual shift mode in an automatic transmission.
The P0959 code is triggered when the Powertrain Control Module (PCM) detects an intermittent issue in the auto shift manual mode circuit. This circuit is responsible for allowing the driver to manually control gear shifts in an automatic transmission. An intermittent fault suggests that the problem may come and go, making it more challenging to diagnose.
• Check Engine Light is on
• Inability to shift manually
• Erratic shifting behavior
• Faulty shift lever assembly
• Damaged wiring or connectors
• Defective transmission control module (TCM)
PCM: Powertrain Control Module
TCM: Transmission Control Module
• Scan the vehicle for trouble codes and freeze frame data.
• Inspect the shift lever assembly for damage or wear.
• Check the wiring and connectors related to the manual shift circuit for damage or corrosion.
• Replace or repair the shift lever assembly if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• Honda Accord
• Toyota Camry
• Ford Fusion
• Regularly inspect and maintain the transmission system.
• Ensure wiring and connectors are free from corrosion.
• Avoid aggressive shifting habits.
Transmission Control Issue
• Avoid manual shifting until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis.
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has been more prevalent in vehicles with higher mileage or those frequently using manual shift mode.
Moderate – It may not immediately affect drivability but should be addressed to prevent further transmission issues.
Driving with transmission issues can lead to safety concerns. Address the problem promptly to ensure vehicle safety.
• Vehicle in park or neutral
• Engine running
The manual shift mode circuit is typically located within the transmission or near the shift lever assembly.
Q: Can I drive my car with a P0959 code?
A: While the car may still be drivable, it's best to have it checked to avoid potential transmission damage.
Q: Will this code affect my car's performance?
A: It may cause erratic shifting or prevent manual shifting, which can affect driving performance.
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