DTC P0030:00, P0050:00 [MZI-3.7]: Notes

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DETECTION CONDITION & POSSIBLE CAUSE

DTC P0030:00 DTC P0050:00	A/F sensor (RH) heater control circuit A/F sensor (LH) heater control circuit
DETECTION CONDITION	P0030:00 indicates that A/F sensor (RH) heater circuit has a malfunction P0050:00 indicates that A/F sensor (LH) heater circuit has a malfunction The PCM monitors the heater in the air fuel ratio (A/F) sensor (RH/LH) for correct operation The PCM controls the heater on/off duty cycle to maintain a temperature of 780°C (1, 436°F). The test fails when the sensor does not warm up to the required temperature in the calibrated amount of time. The test also fails when the PCM is not able to maintain the required temperature after the sensor is warm.
POSSIBLE CAUSE	P0030:00. Short to power supply in wiring harness between PCM terminal 2J and A/F sensor (RH) terminal 4 P0050:00. Short to power supply in wiring harness between PCM terminal 2E and A/F sensor (LH) terminal 4 P0030:00: Open circuit in wiring harness between PCM terminal 2AC and A/F sensor (RH) terminal 5 P0050:00 Open circuit in wiring harness between PCM terminal 2AE and A/F sensor (LH) terminal 5 P0030:00 Open circuit in wiring harness between PCM terminal 2AG and A/F sensor (RH) terminal 3 P0050:00. Open circuit in wiring harness between PCM terminal 2AK and A/F sensor (LH) terminal 3 P0030:00. Open circuit in wiring harness between PCM terminal 2J and A/F sensor (RH) terminal 4 P0050:00. Open circuit in wiring harness between PCM terminal 2E and A/F sensor (LH) terminal 4 A/F sensor loose connection, and damaged or corroded terminals Exhaust temperature significantly higher than expected Damaged A/F sensor (RH/LH) PCM malfunction
Courtesy of MAZDA MOTORS CORP.