Code result
P07CB
Transmission Fluid Thermostat Performance
High severity
What it means
The transmission fluid thermostat (similar in function to a coolant thermostat — opens at a calibrated temperature to route ATF through the cooler) does not regulate temperature within the expected band. Either stuck open (ATF stays cold, friction modifier ineffective) or stuck closed (ATF overheats, oxidising the fluid).
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Thermostat stuck open
highOne of the most commonly reported causes for this code — check this first.
Thermostat stuck closed
mediumA plausible cause — test and verify before replacing parts.
Related help
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