TCM Power Input Signal
The TCM detects an out-of-range supply voltage at its main power input. Battery voltage is too low or too high during operation.
Affected components
- Tcm
- Battery
- Alternator
- Wiring harness
Common causes
- High likelihood: Low battery or alternator fault
- Medium likelihood: Poor TCM ground
Possible symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Diagnostic notes
- The malfunction indicator lamp may illuminate
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.