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

Component Inspection

Inspection Condition	(+) Probe		(-) Probe		Specification
Inspection Condition	Connector	Terminal	Connector	Terminal	Specification
Engine "ON" and Engine Idle.	O2 sensor (up) component side	1 (Virtual Ground)	O2 sensor (UP) connector	2 (Nearest Voltage)	Fig 1
Engine "ON" and Engine Idle.	O2 sensor (UP) connector	3 (Current Pump)	O2 sensor (UP) connector	4 (Current Adjust)	Fig 1

Fig 1: Screen Display - Normal Signal Waveform Of O2 Sensor (UP) At Approx. 2000 RPM

G12692916

Courtesy of KIA MOTORS AMERICA, INC.

Good

Fault might be intermittent and caused either by poor contact in connectors or wiring harness, or it has been repaired and control module memory is not cleared yet. Thoroughly check terminal of battery, all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage. Repair or replace as necessary and then go to "VERIFICATION OF REPAIR " procedure.

No Good

If no problems were found with the circuits or connectors, replace the O2 sensor (UP) and go to "VERIFICATION OF REPAIR " procedure.