Code result
P01F9
Engine Coolant Heater B Control Circuit Driver Current/Temperature Too High
Moderate severity
What it means
Engine Coolant Heater B Control Circuit Driver Current/Temperature Too High: the component is overheating, typically from extended load or slip.
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
Short circuit in heater wiring or element
highOne of the most commonly reported causes for this code — check this first.
Related help
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