DTC P0037-00: Ho2S Heater Control Circuit Low Input (Us): Outline

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0037:00 (PCM, SKYACTIV-G, US) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	HO2S heater control circuit low input
Detection condition	When the PCM controls the HO2S heater, the voltage input to the PCM is too low.
Fail-safe	Stops fuel feedback control
Possible cause	HO2S connector or terminals malfunction F8 15 A fuse malfunction Short to ground in HO2S heater power supply circuit Open circuit in HO2S heater power supply circuit HO2S heater malfunction PCM connector or terminals malfunction Open circuit in HO2S heater control circuit Short to ground in HO2S heater control circuit PCM malfunction
Courtesy of MAZDA MOTORS CORP.