Code result
P07FF
Cold Start Transmission Performance
High severity
What it means
During the cold-start phase the transmission does not behave to specification — typically very slow shifts, missed shifts or harsh engagement at low ATF temperature. Common causes are degraded ATF (lost cold-flow viscosity), a stuck thermostat or aged solenoid drivers.
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
Degraded ATF without cold-flow reserve
highOne of the most commonly reported causes for this code — check this first.
Stuck transmission fluid thermostat
mediumA plausible cause — test and verify before replacing parts.
Related help
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