Powertrain
Definition only
Lights the check engine lamp
P2B72: Coolant Heater A Control Circuit/Open
Standardized SAE J2012 code · P2Bxx codes
What does P2B72 mean?
The control circuit of coolant heater A reports a control circuit/open condition. Auxiliary preheating of the coolant cannot be commanded as expected.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Open in heater control wire
- Medium Open heater element
- Low Pin pushed back out of connector body
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2B72 on the same make and model first.
P2B72 in the community
Ask about P2B72No one has posted about P2B72 yet
Share your vehicle, the tool you used and what you tested — the first thread helps everyone who searches for this code.
Describe your P2B72 problem