Transmission Control System MIL Request
What does P0802 mean?
The P0802 code means the vehicle's onboard diagnostic system has detected: Transmission Control System MIL Request. This is a moderate severity code.
Common Symptoms
- Check Engine Light illuminated
- Transmission may enter limp mode
- Erratic or harsh shifting
- Reduced fuel economy
Probable Causes (Ranked by Likelihood)
- Internal transmission control module fault Very High
- Communication error between TCM and ECM High
- Damaged wiring in TCM circuit Moderate
- Software issue requiring TCM reprogramming Low
Step-by-Step Diagnostic Procedure
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Scan for all stored DTCs in both the ECM and TCM
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Check communication between the ECM and TCM using a bidirectional scan tool
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Inspect TCM connectors and wiring for damage or corrosion
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Verify TCM software version and update if needed
Frequently Asked Questions
What is the difference between P0700 and P0802?
P0700 is a generic transmission fault indicator, while P0802 specifically indicates the TCM has requested the Check Engine Light be turned on due to a transmission control system issue.
Can I reset P0802 and keep driving?
You can clear the code, but if the underlying fault persists, the code will return. It is best to diagnose and fix the root cause.
Will P0802 cause transmission damage?
Driving in limp mode for extended periods can cause additional wear. Have the issue diagnosed promptly to avoid further damage.