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After-Run Coolant Pump - V51-, Checking

General Description

The After-Run Coolant Pump -V51- is cycled on and off by the Engine/Motor Control Module -J623-.

Special tools and workshop equipment required

Multimeter.
Wiring Diagram.
Scan Tool.

Test requirements

Fuses OK.
Battery voltage OK.
Switch OFF all electrical and electronic accessories.
Vehicles with automatic transmission, ensure the selector lever position is in "P".
Vehicles with manual transmission, ensure the shifter lever position is in "N" with the parking brake applied.
Observe all safety precautions: SAFETY PRECAUTIONS .
View clean working conditions: CLEAN WORKING CONDITIONS .

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 After-Run Coolant Pump - V51-, CHECKING => 2 . -- NO: GATHER more information from customer about the complaint.
2	IGNITION: OFF. DISCONNECT: After-Run Coolant Pump -V51- harness connector. IGNITION: ON. CHECK: After-Run Coolant Pump -V51- harness connector terminal 2 to ground for voltage. IGNITION: OFF. SPECIFIED VALUE: Battery voltage. -- Was Value obtained?	-- YES: GO TO: Step 3 After-Run Coolant Pump - V51-, CHECKING => 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 5 After-Run Coolant Pump - V51-, CHECKING => 5 .
3	CHECK: After-Run Coolant Pump -V51- harness connector terminal 1 to ground for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was Value obtained?	-- YES: GO TO: Step 4 After-Run Coolant Pump - V51-, CHECKING => 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 5 After-Run Coolant Pump - V51-, CHECKING => 5 .
4	REMOVE: Engine/Motor Control Module -J623-. Refer to appropriate Service Information. CHECK: After-Run Coolant Pump -V51- harness connector terminal 3 to the Engine/Motor Control Module -J623- harness connector T105 / 69 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was Value obtained?	-- YES: REPLACE: After-Run Coolant Pump -V51-. Refer to appropriate Service Information. GO TO: Step 5 After-Run Coolant Pump - V51-, CHECKING => 5 . -- 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 5 After-Run Coolant Pump - V51-, CHECKING => 5 .
5	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-. Refer to appropriate Service Information. 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.