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 reading the position of the gear shifter. It's like when a video game controller isn't working right and the game can't tell if you're pressing a button.
The P091C code indicates a problem with the circuit that tells the car's computer what gear the car is in. Specifically, it means the signal is too low.
The P091C code is set when the Powertrain Control Module (PCM) detects a low voltage condition in the gear shift position circuit B. This circuit is responsible for transmitting the current gear position to the PCM. A low signal could indicate an issue with the wiring, connectors, or the sensor itself.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may not start
• Faulty gear position sensor
• Damaged wiring or connectors
• Faulty PCM
PCM: Powertrain Control Module, the computer that controls engine and transmission functions.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the gear position sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the gear position sensor if faulty.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect transmission wiring.
• Ensure connectors are secure and free of corrosion.
• Have the transmission system checked during routine maintenance.
Sensor Issue
• Avoid driving the vehicle if it doesn't shift properly.
• Have the vehicle inspected by a professional mechanic.
• Do not attempt repairs without proper tools and knowledge.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with issues in vehicles with electronic gear shift systems, particularly in models with a history of transmission sensor issues.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with a malfunctioning transmission can be dangerous. Ensure repairs are conducted by a qualified professional.
• Vehicle in park with engine running.
• Transmission in various gears to test sensor response.
The gear position sensor is typically located on the transmission housing, near the shift linkage.
Q: Can I drive with a P091C code?
A: It's not recommended to drive with this code as it may cause shifting issues and could lead to further damage.
Q: How do I reset the P091C code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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