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Test Procedure

NOTE:

Prior to beginning the test procedure, make sure to check the items listed below:

Poor fuel quality

Ignition timing malfunction

Loose components on the engine block

Engine temperature must be in the normal range

Step	Procedure	Result / Action to Take
1	PERFORM: Preliminary Check to verify the customers complaint. Refer to: PERFORM: Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK . -- Was Complaint verified?	-- YES: GO TO: Step 2. -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. CONNECT: Scan tool. START: Engine and let Idle. CHECK: The ignition advance timing value. TAP: Near the Knock Sensor 1 -G61- area and monitor for any fluctuations in the ignition timing advance value. IGNITION: OFF. SPECIFIED VALUE: 1 - 10 degrees of ignition timing fluctuation. -- Was Value obtained?	-- YES: CONDITION: May be intermittent. PERFORM: Visual Inspection of wiring and component. CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals. REPAIR: Faulty wiring or connector. GO TO: Step 4. -- NO: GO TO: Step 3.
3	REMOVE: Engine/Motor Control Module - J623-. CHECK: Knock Sensor 1 -G61- harness connector terminal 1 to the Engine/Motor Control Module - J623- harness connector T105 / 51 for resistance. CHECK: Knock Sensor 1 -G61- harness connector terminal 2 to the Engine/Motor Control Module - J623- harness connector T105 / 72 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were Values obtained?	-- YES: TIP: The Knock Sensor 1 -G61- may fail under loaded operation; please swap a known good Knock Sensor 1 -G61- prior to continuing to the next step. GO TO: Step 4. -- NO: PERFORM: Visual Inspection of wiring and component. CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals. REPAIR: Faulty wiring or connector. GO TO: Step 4.
4	Final Procedure Perform a road test to verify repair. -- Does the original DTC return?	-- YES: CHECK: Engine/Motor Control Module -J623- harness connector for any damaged, pushed out pins. REPAIR: As necessary. If all electrical connections are OK: REPLACE: Engine/Motor Control Module -J623-. Clear the DTC's. Refer to: DIAGNOSTIC MODE 04 - ERASE DTC MEMORY . Repair is complete. Generate Readiness Code. Refer to: READINESS CODE . Return vehicle to Customer. -- NO: Perform the diagnostic procedure for any DTC's. If no DTC's return, the repair is complete. Return vehicle to customer.