Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a part in the car that tells the transmission what gear it should be in. It's like a switch that isn't working properly.
The transmission range control sensor/switch is responsible for detecting the position of the gear selector. An open circuit means there is a break in the electrical connection.
The P27EF code indicates that the Transmission Control Module (TCM) has detected an open circuit in the Transmission Range Control B Position Sensor/Switch. This sensor provides feedback to the TCM about the current gear position, and an open circuit can disrupt this communication.
• Check Engine Light is on
• Transmission may not shift correctly
• Vehicle may not start or move
• Faulty transmission range sensor/switch
• Damaged wiring or connectors
• Faulty Transmission Control Module (TCM)
Transmission Control Module (TCM): A computer that controls the transmission's functions.
Open Circuit: A break in the electrical circuit preventing current flow.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the transmission range sensor/switch for proper operation.
• Replace the faulty transmission range sensor/switch.
• Repair or replace damaged wiring or connectors.
• If necessary, replace the Transmission Control Module (TCM).
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain transmission components.
• Avoid harsh driving conditions that may stress the transmission.
• Ensure proper electrical connections and avoid exposure to moisture.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle's manufacturer for warranty coverage on transmission components.
This code has been associated with vehicles experiencing transmission shifting issues due to sensor failures.
Moderate – It is recommended to address this issue soon to avoid potential transmission damage.
Driving with transmission issues can be unsafe and may lead to further damage. Address the issue promptly.
• Vehicle in park or neutral
• Engine running
The transmission range sensor/switch is typically located on the transmission housing.
Q: Can I drive with a P27EF code?
A: It's not recommended to drive with this code as it can lead to transmission issues and unsafe driving conditions.
Q: How do I reset the check engine light after repair?
A: Use an OBD-II scanner to clear the code after the repair is completed.
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