Code result
P21CC
Reductant Control Module Supply Voltage High
Moderate severity
What it means
SCR control module supply voltage above the upper threshold — overvoltage.
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
Charging system overvoltage
highOne of the most commonly reported causes for this code — check this first.
Related help
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