Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the car's computer system that talks to the transmission, and it's asking for the check engine light to turn on.
The P0802 code is triggered when the transmission control module (TCM) requests the malfunction indicator lamp (MIL) to be illuminated due to a detected fault.
The Transmission Control System MIL Request Circuit is responsible for communicating with the engine control module (ECM) to turn on the MIL when a transmission-related fault is detected. An open circuit or fault in this communication line can trigger the P0802 code.
• Check engine light is on
• Transmission may not shift properly
• Possible lack of power
• Faulty transmission control module (TCM)
• Open or shorted wiring in the MIL request circuit
• Poor electrical connection at the TCM
Transmission Control Module (TCM): A computer that controls the transmission's operation.
Malfunction Indicator Lamp (MIL): Also known as the check engine light, it alerts the driver to a fault.
• Use an OBD-II scanner to verify the P0802 code is present.
• Inspect the wiring and connectors related to the TCM for damage or corrosion.
• Test the TCM for proper operation and communication with the ECM.
• Repair or replace damaged wiring or connectors.
• Replace the faulty TCM if necessary.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Honda Accord
• Toyota Camry
• Ford F-150
• Regularly inspect and maintain transmission wiring.
• Keep the transmission control module clean and dry.
• Ensure proper electrical connections are maintained.
Transmission System Issue
• Have the vehicle inspected by a professional if the check engine light is on.
• Avoid driving the vehicle aggressively until the issue is resolved.
Check with the vehicle manufacturer for specific warranty coverage related to the transmission system.
The P0802 code has been recognized as a common issue in vehicles with electronic transmission control systems since the early 2000s.
Moderate – It is recommended to address this issue promptly to avoid further transmission damage.
Driving with a malfunctioning transmission can be unsafe and may lead to further vehicle damage.
• Vehicle must be in a safe location.
• Engine should be off and cool before inspection.
The transmission control module is typically located near the transmission or within the engine compartment.
Q: Can I drive with a P0802 code?
A: It's not recommended to drive for long periods with this code, as it could lead to transmission damage.
Q: How do I clear a P0802 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is resolved first.
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