P0030 - Ho2S Heater Control Circuit (Bank 1, Sensor 1)

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P0030 - HO2S HEATER CONTROL CIRCUIT (BANK 1, SENSOR 1)

Description:	The powertrain control module (PCM) monitors the heater in the heated oxygen sensor (HO2S) 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 a 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 Causes:	Open UO2S circuit Open UO2SGREF circuit Open UO2SHTR circuit UO2SHTR circuit short to voltage Loose connection, and damaged or corroded terminals Exhaust temperature significantly higher than expected Damaged universal HO2S
Diagnostic Aids:	Inspect the connectors for signs of damage, water ingress, or corrosion.
Application		Key On Engine Off	Key On Engine Running	Continuous Memory
All		-	refer to PINPOINT TEST DZ .	refer to PINPOINT TEST DZ .