DTC P0037: Notes

DTC P0037 [L3] CHART

DTC P0037	Rear HO2S heater circuit low input
DETECTION CONDITION	The PCM monitors the rear HO2S heater output voltage. If the PCM turns the rear HO2S heater off or on but the rear HO2S heater circuit remains low voltage, the PCM determines that the rear HO2S heater circuit has malfunction. Diagnostic support note This is a continuous monitor (HO2S heater). MIL illuminates If the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle. FREEZE FRAME DATA is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	Rear HO2S malfunction Open circuit in wiring harness between the IG1 and rear HO2S terminal C Open circuit in wiring harness between rear HO2S terminal D and PCM terminal 2C Short to ground in wiring harness between rear HO2S terminal D and PCM terminal 2C Poor connection at the rear HO2S or the PCM connector PCM malfunction