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 thinks the transmission fluid is hotter than it should be, like when you get a fever and your mom checks your temperature with a thermometer.
The transmission fluid temperature sensor is detecting a temperature that is higher than the expected range.
The P187B code is triggered when the transmission control module (TCM) receives a signal from the transmission fluid temperature sensor 'A' indicating a temperature that is higher than the normal operating range. This can lead to improper transmission operation and potential damage if not addressed.
• Illuminated check engine light
• Transmission overheating warning on the dashboard
• Poor transmission performance or shifting issues
• Faulty transmission fluid temperature sensor
• Wiring issues or poor connections in the sensor circuit
• Overheating transmission fluid due to low fluid levels or poor fluid quality
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
Sensor: A device that detects or measures a physical property and records, indicates, or otherwise responds to it.
• Use an OBD-II scanner to confirm the P187B code.
• Inspect the transmission fluid temperature sensor and its wiring for damage or disconnections.
• Check the transmission fluid level and quality.
• Replace the faulty transmission fluid temperature sensor.
• Repair or replace damaged wiring or connectors.
• Flush and refill the transmission fluid if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Use the recommended transmission fluid type.
• Have periodic transmission inspections.
Sensor Issue
• Avoid driving the vehicle until the issue is diagnosed and repaired.
• Consult a professional mechanic if unsure about the repair process.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been reported in vehicles with high mileage or those that frequently tow heavy loads.
High – Driving with this issue can lead to transmission damage.
Ignoring this code can lead to severe transmission damage and potential safety hazards while driving.
• Vehicle at operating temperature
• Transmission in normal driving conditions
The transmission fluid temperature sensor is typically located within the transmission or attached to the transmission housing.
Q: Can I drive my car with a P187B code?
A: It's not recommended to drive with this code as it may cause further damage to the transmission.
Q: How do I know if my transmission fluid is overheating?
A: You may notice a warning light on the dashboard or experience poor transmission performance.
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