Code result
P2B79
Coolant Heater B Control Circuit Performance
Moderate severity
What it means
The control circuit of coolant heater B reports a control circuit performance condition. Auxiliary preheating of the coolant cannot be commanded as expected.
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
Heater element aged - low output
highOne of the most commonly reported causes for this code — check this first.
Supply voltage low under load
mediumA plausible cause — test and verify before replacing parts.
Related help
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