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 the sensor that measures how fast the wheels are spinning is reporting a speed that's too high.
The output speed sensor measures the rotational speed of the transmission output shaft, and this code is triggered when the sensor reports a speed higher than expected.
The P18AD code is set when the transmission control module (TCM) detects that the output speed sensor is reporting a speed that exceeds the expected range for a given operating condition. This could indicate a malfunction in the sensor or an issue with the transmission itself.
• Check Engine Light is on
• Erratic or harsh shifting
• Transmission slipping
• Faulty output speed sensor
• Wiring issues such as short circuits or open circuits
• Malfunctioning transmission control module
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
Output Speed Sensor: A sensor that measures the speed of the transmission's output shaft.
• Use an OBD-II scanner to confirm the code.
• Inspect the output speed sensor and its wiring for damage.
• Test the sensor's electrical resistance and compare it to specifications.
• Replace the output speed sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance and inspection of transmission components.
• Ensure proper fluid levels and quality.
• Address transmission issues promptly.
Sensor Issue
• Avoid driving at high speeds until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage related to the transmission and sensors.
This code has been associated with vehicles that have experienced transmission issues due to sensor malfunctions or wiring problems.
Moderate – This issue can affect drivability and should be addressed soon to prevent further transmission damage.
Driving with a malfunctioning transmission sensor can lead to unsafe driving conditions. Address the issue promptly.
• Vehicle must be running.
• Transmission should be in drive mode.
The output speed sensor is typically located on the transmission housing, near the output shaft.
Q: Can I drive with a P18AD code?
A: It's not recommended to drive with this code as it can lead to transmission damage or unsafe driving conditions.
Q: How do I reset the P18AD 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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