Code result
P277A
Electric/Auxiliary Transmission Fluid Pump B Hydraulic Leakage
High severity
What it means
The second auxiliary transmission fluid pump cannot maintain pressure even at high duty cycle. Indicates internal hydraulic leakage downstream of the pump.
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
Worn or hardened seals downstream of pump
highOne of the most commonly reported causes for this code — check this first.
Pressure relief or bypass valve stuck open
mediumA plausible cause — test and verify before replacing parts.
Related help
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