Internal Control Module Transmission Gear Select Performance
The internal gear-select interpretation logic in the transmission control module does not match external sensor inputs.
Affected components
- Tcm
Common causes
- Medium likelihood: Internal logic drift after firmware update
- Medium likelihood: External gear-select sensor drift
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.