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 checks how hot the hydraulic oil is might not be working right.
The P0938 code indicates a problem with the hydraulic oil temperature sensor, which is responsible for monitoring the temperature of the hydraulic oil. The sensor's readings are not within the expected range.
The hydraulic oil temperature sensor is part of the vehicle's transmission system. It measures the temperature of the hydraulic oil to ensure it is within the optimal range for operation. If the sensor's output is not within the expected range, the vehicle's computer will trigger the P0938 code.
• Check Engine Light is on
• Transmission may not shift properly
• Possible overheating of hydraulic oil
• Faulty hydraulic oil temperature sensor
• Wiring issues or poor connections
• Malfunctioning transmission control module (TCM)
OBD-II: On-Board Diagnostics, a system for self-diagnosing and reporting vehicle issues.
TCM: Transmission Control Module, the computer responsible for managing transmission functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the sensor.
• Test the hydraulic oil temperature sensor for proper operation.
• Replace the hydraulic oil temperature 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
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance and inspection of transmission components.
• Ensure proper fluid levels and quality.
• Address any transmission issues promptly.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle diagnosed by a professional if unsure.
• Avoid driving the vehicle if transmission issues are severe.
Check with the vehicle manufacturer for specific warranty coverage on transmission components.
This code has been associated with transmission issues in vehicles with electronic control systems for several years.
Moderate – Address the issue to prevent potential transmission damage.
Driving with a malfunctioning transmission sensor can lead to unsafe driving conditions.
• Vehicle at operating temperature
• Transmission in normal operating mode
The hydraulic oil temperature sensor is typically located on or near the transmission housing.
Q: Can I drive with a P0938 code?
A: It's not recommended to drive for extended periods with this code, as it may lead to further transmission damage.
Q: How do I reset the P0938 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, the code should not return.
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