Code result
P278B
Kick Down Switch Circuit Range/Performance
High severity
What it means
The kick-down switch state is implausible against accelerator pedal position. 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
Switch trip point drift
mediumA plausible cause — test and verify before replacing parts.
Accelerator pedal travel out of spec
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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