What does code P2B73 mean?

Q: What does code P2B73 mean?

Coolant Heater A Control Circuit Low. P2B73 means the powertrain control module (PCM) has detected a low-voltage condition on the control circuit for coolant heater A, which is typically a block heater or an electrically heated coolant circuit used to speed cabin warmth and engine warm-up. The PCM commands the heater on and monitors the circuit, and it sets this code when the feedback voltage stays below the expected threshold, indicating a short to ground, an open circuit, or a failed heater element.

DTC codes / P2Bxx · Hybrid propulsion / P2B73

P2B73Coolant Heater A Control Circuit Low

P2B73 means the powertrain control module (PCM) has detected a low-voltage condition on the control circuit for coolant heater A, which is typically a block heater or an electrically heated coolant circuit used to speed cabin warmth and engine warm-up. The PCM commands the heater on and monitors the circuit, and it sets this code when the feedback voltage stays below the expected threshold, indicating a short to ground, an open circuit, or a failed heater element.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaHybrid propulsion

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.