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DTC P2237-00: O2 Sensor Positive Current Control Circuit/Open - Bank 1, Sensor 1 [08/2018 - ]: Contents

DTC No.	Detection Item	DTC Detection Condition	Warning Indicate	Memory	Fail-safe Operation	Note
P223700	O2 Sensor Positive Current Control Circuit/Open - Bank 1, Sensor 1	Open circuit between A/F sensor terminal C6-41, C35-42 and ECM terminal C27-821, C28-32	Check engine light: ON Master warning light: OFF Charging system warning light: OFF Engine oil warning light: OFF Wrench warning indicator light: OFF	DTC stored	Applicable	Drive cycle: 2 Monitor item: A/F sensor, HO2S Self test type: CMDTC self test, KOER self test

*1: 200 Pin Type

*2: 186 Pin Type

DETAILS ON DTCS (200 PIN TYPE)

DTC DETECTION CONDITION	Open circuit between A/F sensor terminal C6-4 and ECM terminal C27-82
	Determination conditions	After A/F sensor activation, a condition in which ECM terminal C27-81 voltage is within the specified range continues for 5 s or more.
	Preconditions	Battery voltage: 11-18 V* The following DTC is not detected: Internal ECM malfunction: P064D00 *: Value can be verified by displaying PIDs using Techstream
	Drive cycle	2
	Self test type	CMDTC self test, KOER self test
	Sensor used	A/F sensor
FAIL-SAFE OPERATION	Fixes duty value of A/F sensor heater Stops fuel feedback control of A/F sensor
VEHICLE STATUS WHEN DTCS ARE OUTPUT	Illuminates check engine light.
TROUBLE AREA	A/F sensor connector or terminals malfunction ECM connector or terminals malfunction Open circuit in wiring harness between A/F sensor terminal C6-4 and ECM terminal C27-82 A/F sensor malfunction ECM malfunction

DETAILS ON DTCS (186 PIN TYPE)

DTC DETECTION CONDITION	Open circuit between A/F sensor terminal C35-4 and ECM terminal C28-3
	Determination conditions	After A/F sensor activation, a condition in which ECM terminal C28-4 voltage is within the specified range continues for 5 s or more.
	Preconditions	Battery voltage: 11-18 V* The following DTC is not detected: Internal ECM malfunction: P064D00 *: Value can be verified by displaying PIDs using Techstream
	Drive cycle	2
	Self test type	CMDTC self test, KOER self test
	Sensor used	A/F sensor
FAIL-SAFE OPERATION	Fixes duty value of A/F sensor heater Stops fuel feedback control of A/F sensor
VEHICLE STATUS WHEN DTCS ARE OUTPUT	Illuminates check engine light.
TROUBLE AREA	A/F sensor connector or terminals malfunction ECM connector or terminals malfunction Open circuit in wiring harness between A/F sensor terminal C35-4 and ECM terminal C28-3 A/F sensor malfunction ECM malfunction