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 is getting a strange reading from the sensor that checks how hot the transmission fluid is. It's like the sensor is saying the fluid is super hot or super cold when it shouldn't be.
The transmission fluid temperature sensor 'A' is sending a signal to the engine control module (ECM) that doesn't make sense based on the expected operating conditions.
The P186C code is triggered when the Transmission Control Module (TCM) detects an implausible signal from the transmission fluid temperature sensor 'A'. This sensor monitors the temperature of the transmission fluid to ensure it is within the optimal range for operation. An implausible signal may indicate a sensor malfunction, wiring issue, or a problem with the transmission fluid itself.
• Check Engine Light is on
• Transmission may shift erratically
• Poor fuel economy
• Transmission overheating
• Faulty transmission fluid temperature sensor
• Wiring issues or poor connections
• Malfunctioning Transmission Control Module (TCM)
• Contaminated or incorrect transmission fluid
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
Transmission Fluid: A liquid that lubricates and cools the transmission components.
• Scan the vehicle with an OBD-II scanner to confirm the code.
• Inspect the transmission fluid temperature sensor and its wiring.
• Check the transmission fluid level and condition.
• Test the sensor with a multimeter for proper operation.
• Replace the faulty transmission fluid temperature sensor.
• Repair or replace damaged wiring or connectors.
• Flush and replace the transmission fluid if contaminated.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Inspect and replace transmission fluid as recommended by the manufacturer.
• Ensure all electrical connections are secure and free of corrosion.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult with a professional mechanic for an accurate diagnosis.
Check with your vehicle manufacturer; the transmission sensor may be covered under powertrain warranty.
This code has been reported in vehicles with high mileage or those that have not had regular transmission maintenance.
Moderate – It is advisable to address this issue soon to avoid potential transmission damage.
Ignoring this code can lead to transmission failure, which may pose a safety risk while driving.
• Vehicle at operating temperature
• Transmission fluid at optimal level
The transmission fluid temperature sensor is typically located inside the transmission or near the transmission fluid pan.
Q: Can I drive with a P186C code?
A: It's not recommended to drive with this code as it may lead to transmission damage.
Q: How often should I check my transmission fluid?
A: Check your transmission fluid level and condition every 30,000 to 60,000 miles, or as recommended by your vehicle's manufacturer.
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