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 temperature sensor for the transmission fluid is showing a temperature that's too low. It's like when a thermometer says it's really cold, but it shouldn't be.
The P18DA code indicates that the transmission fluid temperature sensor 'B' is reporting a temperature reading that is lower than the expected range.
The transmission fluid temperature sensor 'B' provides the transmission control module (TCM) with the temperature of the transmission fluid. This information is crucial for the TCM to manage transmission operations effectively. If the sensor reports a temperature that is too low, it could indicate a sensor malfunction, wiring issue, or actual low fluid temperature.
• Check Engine Light illumination
• Poor transmission performance
• Transmission overheating
• Faulty transmission fluid temperature sensor
• Wiring issues such as shorts or opens in the circuit
• Low transmission fluid level
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 code.
• Inspect the transmission fluid temperature sensor and its wiring.
• Check the transmission fluid level and condition.
• Replace the faulty transmission fluid temperature sensor.
• Repair or replace damaged wiring or connectors.
• Refill or replace the transmission fluid if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly check transmission fluid levels.
• Perform routine maintenance on the transmission system.
• Inspect wiring and connectors for damage periodically.
Sensor Issue
• Avoid driving aggressively until the issue is resolved.
• Have the vehicle inspected by a professional if unsure about repairs.
Check if the vehicle's powertrain warranty covers sensor replacements.
This code has been reported in vehicles with aging transmission systems, often due to sensor wear or wiring issues.
Moderate – Address the issue soon to prevent potential transmission damage.
Driving with a faulty sensor may lead to transmission damage, which can be costly to repair.
• Engine at operating temperature
• Vehicle in park or neutral
The transmission fluid temperature sensor is typically located on or near the transmission pan.
Q: Can I drive with a P18DA 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 P18DA code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, the code should not return.
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