Transmission Control Module (TCM) - Data Validity
The TCM has detected a data validity issue.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The Transmission Control Module is seeing data it considers false or inconsistent, often due to faulty sensors or bad wiring.
What the computer is actually seeing
The TCM monitors data inputs from various sensors for transmission operation. When it sees values out of the expected range or mismatched, it flags this code. For example, if the transmission input speed sensor shows 0 RPM when the vehicle is moving, that creates a conflict.
What a healthy reading looks like
Typical input speed sensor values should be between 0-8000 RPM when the vehicle is in motion, and the output should sync closely with engine RPM.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the transmission fluid level and condition; top off or change if necessary (should be a clear, reddish color). Decision: Is fluid okay? Yes: Go to step 2. No: Fix fluid issue first.
- 22. Inspect wiring and connectors related to the TCM and sensors; look for corrosion or damage. Decision: Are connections solid? Yes: Go to step 3. No: Repair/replace wiring or connectors.
- 33. Test the input and output speed sensors with a multimeter; input should match vehicle speed within 5%. Decision: Are sensor readings valid? Yes: Go to step 4. No: Replace the faulty sensor.
- 44. If all other checks are good, consider reprogramming or replacing the TCM if no faults are found in hardware. Decision: Is vehicle operating correctly now? Yes: End. No: Further diagnosis may be needed.
Common causes
- Faulty transmission speed sensor (input or output)
- Bad wiring or connector issues to the TCM
- Transmission fluid level low or contaminated
- Faulty TCM software or hardware issues
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable but may have issues with shifting or performance; fix it soon.
Will this code come back after clearing?
It can come back if the underlying issue isn't addressed.
Why does this code sometimes pair with other codes?
Other codes may indicate related sensor or system failures that affect transmission performance.
Working a real vehicle right now?
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