Code result
P0378
Timing Reference High Resolution Signal B Intermittent/Erratic Pulses
High severity
What it means
Timing reference signal B pulses are erratic — connector or wiring intermittent, contamination on tone wheel, or sensor partially failed.
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
Intermittent connector or contamination
highOne of the most commonly reported causes for this code — check this first.
Connector with intermittent contact under vibration
lowLess common, but worth ruling out after the more likely causes.
Harness routed against vibrating component
lowLess common, but worth ruling out after the more likely causes.
Related help
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