Transmission Control Module (TCM) Power Input Signal Low
The TCM is not getting the proper power input signal.
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 (TCM) isn’t receiving enough power to operate properly, which can lead to transmission issues.
What the computer is actually seeing
The TCM detects that the voltage supplied to it falls below the minimum threshold, typically below 10 volts during engine operation.
What a healthy reading looks like
Normal voltage at the TCM should be between 11-14 volts while the engine is running, and not drop below 10 volts during this time.
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. Inspect the TCM connector for corrosion or loose pins.
- 22. Check the voltage at the TCM connector with a multimeter; should be 11-14 volts with the engine running.
- 33. If voltage is low, check the vehicle's battery and charging system for faults.
- 44. Test the TCM power circuit for continuity issues; repair any broken wiring as necessary.
- 55. If all wiring and power are good, replace the TCM.
Common causes
- Faulty Transmission Control Module
- Bad wiring or connectors leading to the TCM
- Weak battery or charging system
- Blown fuse for the TCM circuit
- Corrosion or damage in the connector pins
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best not to drive as this can lead to transmission slipping or failure.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, the code will likely return.
Why might this code pair with others?
Codes like P0700 might indicate a generic transmission issue, while others could point to specific sensor problems.
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