DTC P0053-00: A/F Sensor Heater Resistance: Notes

WARNING: This page is about a different car, the 2016 Mazda CX-5. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0053:00	A/F sensor heater resistance
DETECTION CONDITION	The PCM monitors the A/F sensor heater resistance when under the A/F sensor heater control. If the resistance is more than 30 ohms , the PCM determines that there is a A/F sensor circuit problem. Diagnostic support note This is an intermittent monitor (A/F sensor heater, HO2S heater). 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. DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	Stops fuel feedback control
POSSIBLE CAUSE	A/F sensor connector or terminals malfunction A/F sensor heater malfunction Short to ground or open circuit in A/F sensor heater power supply circuit Short to ground in wiring harness between ENGINE1 15 A fuse and A/F sensor terminal A ENGINE1 15 A fuse malfunction Open circuit in wiring harness between main relay terminal C and A/F sensor terminal A PCM connector or terminals malfunction Short to ground in wiring harness between A/F sensor terminal E and PCM terminal 1BY Open circuit in wiring harness between A/F sensor terminal E and PCM terminal 1BY PCM malfunction