Code result
P01E9
Engine Coolant Heater A Control Circuit Low
Moderate severity
What it means
Engine Coolant Heater A Control Circuit Low: the control-circuit voltage is below the expected range. Often a short to ground or high resistance in the wiring.
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
Wiring shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Harness chafing through insulation
lowLess common, but worth ruling out after the more likely causes.
Related help
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