Test Procedure

Step	Procedure	Result / Action to Take
1	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. REMOVE: Reducing Agent Metering System Relay -J963- Refer to appropriate service information. DISCONNECT: Reducing Agent Metering System Delivery Unit -GX19- harness connector. CONNECT: Jumper wire, Reducing Agent Metering System Relay -J963- socket terminals 3 and 5. IGNITION: ON. CHECK: Reducing Agent Metering System Delivery Unit -GX19- wiring connector terminals T4 / 1 and T4 / 4 and T5 / 3 to ground for voltage. IGNITION: OFF. SPECIFIED VALUE: Battery voltage. -- Were Values obtained?	-- YES: GO TO: Step 3. -- 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.
3	REMOVE: Jumper wire, Reducing Agent Metering System Relay -J963- socket terminals 3 and 5. REMOVE: Engine Control Module -J623- harness connector. Refer to appropriate service information. CHECK: Reducing Agent Metering System Delivery Unit -GX19- harness connector terminal T4 / 3 to the Engine Control Module -J623- harness connector terminal T94 / 50 for resistance. CHECK: Reducing Agent Metering System Delivery Unit -GX19- harness connector terminal T4 / 2 to the Engine Control Module -J623- harnessl connector terminal T94 / 28 for resistance. CHECK: Reducing Agent Metering System Delivery Unit -GX19- harness connector terminal T5 / 5 to the Engine Control Module -J623- harness connector terminal T94 / 18 for resistance. CHECK: Reducing Agent Metering System Delivery Unit -GX19- harness connector terminal T5 / 1 to ground for resistance. CHECK: Reducing Agent Metering System Delivery Unit -GX19- harness connector terminal T5 / 4 to ground for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was value obtained?	-- YES: REPLACE: Reducing Agent Metering System Delivery Unit -GX19-. Refer to appropriate service information. 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 Control Module -J623- harness connector for any damaged, pushed-out pins. REPAIR: As necessary. 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. If all electrical connections are OK: REPLACE: Engine Control Module -J623-. Refer to appropriate service information. 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.