Code result
P28C2
Ion Sense Module Supply Voltage High
Moderate severity
What it means
Supply voltage on the ion sense module is above the expected window. Charging system overvoltage or upstream regulator fault.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Alternator regulator drift - overvoltage
highOne of the most commonly reported causes for this code — check this first.
Supply wire shorted to B+
mediumA plausible cause — test and verify before replacing parts.
Related help
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