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 signal that the temperature of the hydraulic oil is too high. It's like when a thermometer shows a very high temperature, which might be wrong.
The P0940 code is triggered when the powertrain control module (PCM) detects a high voltage signal from the hydraulic oil temperature sensor circuit, indicating a potentially high temperature reading.
The hydraulic oil temperature sensor monitors the temperature of the hydraulic oil used in the transmission system. A high circuit signal could mean the sensor is reading a higher than expected temperature, or there might be an electrical issue such as a short circuit.
• Check engine light is on
• Transmission overheating warning
• Poor transmission performance
• Faulty hydraulic oil temperature sensor
• Wiring issues such as shorts or open circuits
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the P0940 code.
• Inspect the wiring and connectors for damage or corrosion.
• 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 PCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance of the transmission system
• Ensure proper fluid levels
• Inspect wiring for damage regularly
Sensor Issue
• Avoid driving aggressively until the issue is resolved.
• Schedule a repair with a qualified mechanic.
• Monitor the vehicle for any unusual transmission behavior.
Check your vehicle's warranty coverage, as sensor issues may be covered under powertrain warranties.
This code has been associated with transmission issues in vehicles with high mileage or inadequate maintenance.
Moderate – Address the issue soon to prevent potential transmission damage.
Ignoring this code can lead to transmission failure, which might cause safety hazards.
• Vehicle must be at operating temperature.
• Engine running and transmission engaged.
The hydraulic oil temperature sensor is typically located on or near the transmission housing.
Q: Can I drive with a P0940 code?
A: It's not recommended to drive for extended periods with this code, as it may lead to transmission damage.
Q: How can I prevent P0940 from occurring?
A: Regular maintenance and ensuring proper fluid levels can help prevent this issue.
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