Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's computer is having trouble talking to a part that helps it know what gear the car is in. It's like when a walkie-talkie has a weak signal.
The code P27E9 indicates that the transmission control module (TCM) has detected a low voltage condition in the transmission range control circuit B.
The transmission range control circuit B is responsible for sending signals to the TCM about the current gear position. A 'low' condition means the voltage is below the expected range, which can affect gear shifting and transmission performance.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may not start or move
• Faulty transmission range sensor
• Damaged wiring or connectors in the circuit
• Faulty transmission control module (TCM)
Transmission Control Module (TCM): A computer that controls the transmission's operation.
OBD-II: On-Board Diagnostics, a standardized system in vehicles for diagnosing issues.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the transmission range sensor for proper operation.
• Replace or repair damaged wiring or connectors.
• Replace the faulty transmission range sensor.
• Replace or reprogram the TCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain transmission components.
• Ensure connectors and wiring are free from corrosion.
• Perform regular transmission fluid changes.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle if transmission issues are severe.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with vehicles experiencing intermittent transmission issues due to sensor failures.
Moderate – Should be addressed soon to avoid potential transmission damage.
Ignoring transmission issues can lead to unsafe driving conditions. Always address Check Engine Light warnings promptly.
• Vehicle at operating temperature
• Transmission in various gear positions
The transmission range sensor is typically located on the side of the transmission housing.
Q: Can I drive with a P27E9 code?
A: It's not recommended to drive for long periods with this code as it can lead to transmission issues.
Q: How do I reset the P27E9 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, it should not return.
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