Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer thinks the transmission fluid is too cold. It's like when you try to swim in a pool that's too chilly.
The transmission fluid temperature sensor is reporting a temperature that is lower than expected, which could affect the transmission's performance.
The P187A code indicates that the Transmission Control Module (TCM) has detected a signal from the transmission fluid temperature sensor 'A' that suggests the fluid is too cold. This could be due to a faulty sensor, wiring issues, or an actual low fluid temperature.
• Check Engine Light is on
• Transmission not shifting properly
• Poor fuel economy
• Faulty transmission fluid temperature sensor
• Wiring issues or poor electrical connections
• Low ambient temperature affecting sensor readings
Transmission: A system in the 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 code.
• Inspect the transmission fluid temperature sensor and its wiring.
• Check the actual transmission fluid temperature with a thermometer.
• Replace the transmission fluid temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Ensure the transmission fluid is at the correct temperature range.
• OBD-II scanner
• Digital multimeter
• Infrared thermometer
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check transmission fluid levels.
• Keep the vehicle in a garage during extremely cold weather.
• Perform regular maintenance on the transmission system.
Sensor Issue
• Avoid driving aggressively until the issue is resolved.
• Schedule a service appointment with a mechanic.
• Monitor the vehicle's performance for any changes.
Check vehicle warranty for coverage on transmission components.
This code has been reported in vehicles operating in colder climates, often during winter months.
Moderate – It should be addressed soon to prevent potential transmission damage.
Ignoring this code could lead to transmission issues, affecting vehicle safety.
• Vehicle at operating temperature
• Cold weather conditions
The transmission fluid temperature sensor is typically located on or near the transmission housing.
Q: Can I drive with a P187A code?
A: It's not recommended to drive for extended periods with this code, as it may lead to transmission issues.
Q: How do I reset the P187A code?
A: You can reset the code using an OBD-II scanner, but it's important to fix the underlying issue first.
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