Code result
P28C0
Ion Sense Module Supply Voltage Circuit
Moderate severity
What it means
The ECM detects a generic fault on the supply voltage circuit of the ion sense module. The module can no longer reliably bias the spark plug for ion current measurement.
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
Module supply rail interrupted
highOne of the most commonly reported causes for this code — check this first.
Wiring or connector fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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