Cause
Blocked or restricted transmission fluid cooler
The heat exchanger that keeps transmission fluid within its working temperature, no longer passing enough flow.
Heat is what kills automatic transmissions, and the relationship is steep: fluid life roughly halves for every 10 °C above its design temperature. A cooler that has stopped working does not announce itself — the car drives normally and the damage accumulates invisibly until something slips.
It blocks from both sides, and the outside is free to check. Externally it sits in the airflow at the front of the car collecting leaves, insects and road debris. Internally it clogs with the debris of an earlier transmission problem, which is why a cooler must be flushed or replaced after any failure that put material into the fluid — fitting a rebuilt gearbox onto a cooler full of the old one's debris is a well-known way to destroy both.
A stuck thermostatic bypass is the third case. Many coolers are bypassed until the fluid warms, to avoid the losses of thick cold fluid; a bypass that never closes means the cooler is plumbed in and never used.
It is cheap to inspect and near the top of the list for any over-temperature code, precisely because nothing about the way the car drives will point at it.
Typically specialist work. Needs equipment or training most home workshops do not have.
Some of these codes mean you should stop driving
11 of the 17 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (17)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0218 Transmission Fluid Temperature Sensor A Over Temperature Condition Likely for this code Stop driving High
- P270A Transmission Friction Element A Temperature Too High Likely for this code Stop driving High
- P270B Transmission Friction Element B Temperature Too High Likely for this code Stop driving High
- P270C Transmission Friction Element C Temperature Too High Likely for this code Stop driving High
- P270D Transmission Friction Element D Temperature Too High Likely for this code Stop driving High
- P270E Transmission Friction Element E Temperature Too High Likely for this code Stop driving High
- P270F Transmission Friction Element F Temperature Too High Likely for this code Stop driving High
- P273F Transmission Fluid Temperature Sensor B Over Temperature Condition Likely for this code Stop driving High
- P274F Transmission Fluid Temperature Sensor C Over Temperature Condition Likely for this code Stop driving High
- P2753 Transmission Fluid Cooler Control Circuit/Open Likely for this code High
- P2754 Transmission Fluid Cooler Control Circuit Low Likely for this code High
- P2755 Transmission Fluid Cooler Control Circuit High Likely for this code High
- P275F Transmission Fluid Temperature Sensor D Over Temperature Condition Likely for this code Stop driving High
- P2783 Torque Converter Temperature Too High Likely for this code Stop driving High
- P0711 Transmission Fluid Temperature Sensor A Circuit Range/Performance Moderate
- P0897 Transmission Fluid Deteriorated Moderate
- P0C1B Electric/Auxiliary Transmission Fluid Pump Control Module Internal Temperature Too High High
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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