Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means the car's computer is having trouble understanding the position of the gear shift. It's like when you can't tell if a light switch is on or off.
The vehicle's transmission control module (TCM) has detected a problem with the gear shift position sensor circuit B, indicating performance outside the expected range.
P091B indicates that the transmission control module (TCM) has identified an issue with the gear shift position sensor circuit B. This sensor is responsible for providing feedback on the position of the gear shift. The issue could be due to electrical problems, sensor failure, or mechanical issues within the transmission.
• Check Engine Light is on
• Difficulty in shifting gears
• Transmission stuck in a single gear
• Faulty gear shift position sensor
• Wiring issues in the circuit
• Malfunctioning transmission control module (TCM)
Transmission Control Module (TCM): An electronic device that controls the transmission functions.
Gear Shift Position Sensor: A sensor that detects the position of the gear shift lever.
• Use an OBD-II scanner to confirm the code
• Inspect the gear shift position sensor and its wiring
• Test the transmission control module for faults
• Replace the faulty gear shift position sensor
• Repair or replace damaged wiring
• Reprogram or replace the transmission control module
• OBD-II scanner
• Multimeter
• Screwdriver set
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain transmission components
• Ensure proper electrical connections
• Avoid harsh driving conditions
Sensor Issue
• Do not ignore the Check Engine Light
• Get the vehicle diagnosed by a professional
• Avoid driving the vehicle until repaired
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been known to appear in vehicles with high mileage or those that have experienced electrical issues.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with transmission issues can lead to unsafe driving conditions. Address this code promptly to ensure vehicle safety.
• Vehicle at operating temperature
• Transmission in drive mode
The gear shift position sensor is typically located on the transmission housing or near the gear shift lever.
Q: Can I drive with a P091B code?
A: It's not recommended to drive with this code as it may cause further transmission damage.
Q: How can I reset the P091B code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue persists, further diagnosis is needed.
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