Transmission Fluid Cooler Control Circuit High
What it means
P2755 means the control module detected high voltage (usually an open) in the transmission fluid cooler control circuit — the circuit that manages how fluid flows through the cooler to regulate transmission temperature. The engine runs normally, but if cooling isn't controlled the transmission can overheat under load, so it's worth fixing before towing or hard driving. The cause is typically wiring, a connector, or a failed control valve.
Can I keep driving? The engine runs and the car drives, but if the fluid cooler isn't controlled properly the transmission can overheat under load. Avoid towing or hard driving until fixed.
Common symptoms
What you'll notice
- Check-engine light on
- Transmission running hotter than normal, especially under load
- Possible shifting problems if the transmission overheats
- Often no obvious symptom in light driving
Common causes
Most likely first
- High voltage / open in the transmission fluid cooler control circuitLikely
- Corroded, loose, or damaged connector at the cooler control valve/solenoidCommon
- Chafed or broken control wiringCommon
- Failed cooler control valve or solenoidLess often
- Faulty ECM/TCM driver (less common)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and inspect the cooler control circuit wiring and connector for an open or corrosion.
- Test the control valve/solenoid's resistance and its supply voltage.
- Repair damaged wiring or replace the cooler control component as needed.
- Check that transmission fluid level and cooling flow are normal.
- Clear the code and monitor transmission temperature on a road test.
FAQ
Quick answers
Is it safe to drive with P2755?+
Can I just clear P2755?+
Related codes
Often seen with P2755
Read & clear P2755 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.