Internal Control Module Transmission Gear Ratio Control Performance
The internal gear ratio control logic in the transmission control module does not produce the expected commands.
Affected components
- Tcm
Common causes
- High likelihood: Internal software logic fault
- Medium likelihood: Memory corruption in TCM
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.