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 thinks there's too much electricity going through a part of the transmission. It's like when you plug too many things into a power strip and it gets really hot.
The transmission current sensor monitors the electrical current in the transmission. If the sensor detects a current that is too high, it triggers the P18FA code.
The P18FA code indicates that the transmission control module (TCM) has detected a high voltage condition in the transmission current sensor circuit. This could be due to a short circuit or a malfunctioning sensor.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may go into limp mode
• Faulty transmission current sensor
• Short circuit in the sensor wiring
• Faulty transmission control module (TCM)
Transmission Control Module (TCM): A computer that controls the transmission functions in a vehicle.
Limp Mode: A safety feature that limits the vehicle's performance to prevent damage.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connections to the transmission current sensor
• Test the transmission current sensor for proper function
• Replace the transmission current sensor if faulty
• Repair or replace damaged wiring
• Replace the transmission control module if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect electrical connections
• Avoid overloading the vehicle
• Perform routine transmission maintenance
Sensor Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving the vehicle if it goes into limp mode
Check with the vehicle manufacturer for warranty coverage on the transmission and related components.
This code is relatively uncommon and typically associated with vehicles that have experienced electrical issues in the transmission system.
Moderate – It is advisable to address this issue soon to avoid potential transmission damage.
Driving with a malfunctioning transmission can be dangerous and may lead to further damage. It is important to have the issue diagnosed and repaired promptly.
• Vehicle must be running
• Transmission must be in operation
The transmission current sensor is typically located on or near the transmission housing.
Q: Can I drive my car with a P18FA code?
A: It's best to have the issue checked as soon as possible. Driving with this code could lead to transmission problems.
Q: What happens if I ignore the P18FA code?
A: Ignoring this code can lead to transmission damage and more costly repairs.
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