Code result
P2779
Downshift Switch Circuit Range/Performance
High severity
What it means
The downshift switch signal is implausible. Stuck or noisy contacts. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
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
Contamination on switch contacts
mediumA plausible cause — test and verify before replacing parts.
Worn switch contacts
mediumA plausible cause — test and verify before replacing parts.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Related help
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