April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit Inspection

Fig 1: ECM System Circuit

G12330445

Courtesy of KIA MOTORS AMERICA, INC.

INSPECTION PART - O2 SENSOR (DOWN) AND ECM CONNECTORS INSPECTION

Inspection Condition	(+) Probe		(-) Probe		Specification
Inspection Condition	Connector	Terminal	Connector	Terminal	Specification
Ignition "OFF". Disconnect the battery (-) cable. Disconnect the electrical connector(s) from the component and ECM.	O2 sensor (DOWN) connector	1 (sensor signal)	Chassis ground	-	∞ (infinite)Ω
	O2 sensor (DOWN) connector	2 (sensor ground)	Chassis ground	-	∞ (infinite)Ω
	O2 sensor (DOWN) connector	1 (sensor signal)	ECM connector	60 (sensor signal)	Approx. below 1Ω
	O2 sensor (DOWN) connector	2 (sensor ground)	ECM connector	45 (sensor ground)	Approx. below 1Ω
Disconnect the electrical connector(s) from the concerned component. Ignition "ON".	O2 sensor (DOWN) connector	1 (sensor signal)	Chassis ground	-	Approx. 0V
	O2 sensor (DOWN) connector	2 (sensor ground)	Chassis ground	-	Approx. 0V

Good	Go to "Component Inspection " procedure.
No Good	Repair open or short in circuit and then go to "Verification Of Repair " procedure.