Transmission Fluid Level Too High
The transmission fluid level monitor reports overfill above the safe maximum. Causes range from incorrect refill at service to coolant intrusion via a failed transmission cooler. Overfilling can cause foaming, accelerated wear and seal damage from raised internal pressure.
Affected components
- Transmission fluid
- Transmission cooler
Common causes
- High likelihood: Overfilled at last service
- Medium likelihood: Coolant intrusion through a failed transmission cooler
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.