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 having trouble reading the pressure of the transmission fluid. It's like trying to read a book with smudged glasses.
The transmission fluid pressure sensor/switch C circuit is not sending the expected signals to the engine control module (ECM).
The P0870 code indicates a malfunction in the transmission fluid pressure sensor/switch C circuit. This sensor monitors the hydraulic pressure in the transmission to ensure proper operation. If the ECM detects an abnormal voltage or resistance in this circuit, it triggers the P0870 code.
• Check Engine Light is on
• Transmission may not shift properly
• Poor fuel economy
• Faulty transmission fluid pressure sensor/switch
• Damaged or corroded wiring/connectors
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to verify the code.
• Inspect the transmission fluid pressure sensor and wiring for damage.
• Test the sensor's voltage and resistance.
• Replace the faulty transmission fluid pressure sensor.
• Repair or replace damaged wiring/connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Inspect wiring and connectors for corrosion.
• Perform routine transmission maintenance.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer for specific warranty coverage on transmission components.
This code has been associated with transmission issues in vehicles with higher mileage or poor maintenance history.
Moderate – It should be addressed soon to prevent further transmission damage.
Ignoring this code may lead to transmission failure, which can be a safety hazard.
• Vehicle in park or neutral
• Engine at operating temperature
The transmission fluid pressure sensor is typically located on the transmission housing.
Q: Can I drive with a P0870 code?
A: It's not recommended to drive with this code as it may lead to transmission damage.
Q: How can I prevent a P0870 code?
A: Regular maintenance and fluid checks can help prevent this issue.
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