P0883: Transmission Control Module Power Input Signal High
What to do
This is very likely a charging system fault affecting the whole car rather than a transmission problem. If the headlights seem unusually bright or the battery warning light is on, have the charging system checked urgently — sustained overvoltage damages electronic modules permanently, and the cost of waiting is not confined to the gearbox.
What this code means
The transmission module's supply voltage is above what it expects. Almost always a charging system fault rather than anything in the transmission — a voltage regulator that has failed to limit output, which raises the supply to every module in the vehicle at once.
Overvoltage is less forgiving than undervoltage. Where a starved module misbehaves and recovers, sustained overvoltage damages electronics permanently, boils a battery and shortens the life of every lamp and module fitted. A transmission code is simply where it happened to be noticed, and treating it as a transmission problem misses a fault that is currently damaging the whole vehicle.
A battery warning lamp or unusually bright headlights alongside this code confirm the reading immediately.
Likely causes
Start here
- Faulty alternator · moderate
- Faulty alternator voltage regulator · moderate
Less common
- Poor module ground connection · moderate
- Wiring shorted to voltage · moderate
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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