Code result
P2B73
Coolant Heater A Control Circuit Low
Moderate severity
What it means
The control circuit of coolant heater A reports a control circuit low 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
Control wire shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Heater element shorted
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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