DTC P2237-00: A/F Sensor Positive Current Control Circuit Open: Notes

DTC P2237:00 DETECTION CONDITION AND POSSIBLE CAUSE

DTC P2237:00	A/F sensor positive current control circuit open
DETECTION CONDITION	The PCM monitors A/F sensor positive current control circuit voltage. If the voltage out of the specified value while the engine is running, the PCM determines that the A/F sensor positive current control circuit is open. Diagnostic support note This is a continuous monitor (A/F sensor, HO2S). The check engine light 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 first drive cycle. FREEZE FRAME DATA (Mode 2)/Snapshot data is available. The DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	Fixes the duty value of the A/F sensor heater. Stops the fuel feedback control.
POSSIBLE CAUSE	A/F sensor connector or terminals malfunction PCM connector or terminals malfunction Open circuit in wiring harness between A/F sensor terminal 1A and PCM terminal 2AD A/F sensor malfunction PCM malfunction
Courtesy of MAZDA MOTORS CORP.