Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, Checking

General Description

The Engine Control Module -J623- tells the Fuel Pump Control Module -J538- the demand needed for fuel volume and pressure and activates the Fuel Delivery Unit -GX1-. The Fuel Delivery Unit -GX1- transfers fuel to the rest of the fuel system, where it is monitored by the Engine Control Module -J623- through sensors, and controlled through regulators and/or metering valves.

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 Auto. Transmission, ensure Selector Lever position is in "P".
Vehicles with Man. Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied.
Observe all safety precautions: SAFETY PRECAUTIONS .
View clean working conditions: CLEAN WORKING CONDITIONS .

Test Procedure

NOTE:

When the door is opened or the Ignition is turned to the ON position the fuel pump is activated for 2 seconds to build up the pressure in the fuel system.

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 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 3 . NO: GATHER more Information from customer about the complaint.
2	IGNITION: ON. LISTEN: Fuel Delivery Unit -GX1- Should be heard running for 2 s. SPECIFIED VALUE: Transfer Fuel Pump ON for 2 s. IGNITION: OFF. -- 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 7 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 7 . NO: GO TO: Step 3 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 3 .
3	IGNITION: OFF. DISCONNECT: Fuel Pump Control Module. -J538- IGNITION: ON. CHECK: Fuel Pump Control Module -J538- harness connector terminals 4 to 5 for voltage. CHECK: Fuel Pump Control Module -J538- harness connector terminal 4 to battery voltage for voltage. A8 ONLY: CHECK: Fuel Pump Control Module -J538- harness connector terminals 6 to 12 for voltage. CHECK: Fuel Pump Control Module -J538- harness connector terminal 6 to battery voltage for voltage. IGNITION: OFF. SPECIFIED VALUE: Battery voltage. -- Were Values obtained?	-- YES: GO TO: Step 4 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, 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 7 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 7 .
4	RECONNECT: Fuel Pump Control Module -J538-. DISCONNECT: Fuel Delivery Unit -GX1-. CRANK: Engine. CHECK: Fuel Delivery Unit -GX1- harness connector terminals 2 to 4 for voltage while engine is cranking. A8 ONLY: CHECK: Fuel Delivery Unit -GX1- harness connector terminals 2 to 5 for voltage while engine is cranking. IGNITION: OFF. SPECIFIED VALUE: 7 - 11 V. -- Was Value obtained?	-- YES: REPLACE: Fuel Delivery Unit -GX1-, Refer to the appropriate service information. GO TO: Step 7 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 7 . NO: GO TO: Step 5 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 5 .
5	DISCONNECT: Fuel Pump Control Module -J538-. CHECK: Fuel Delivery Unit -GX1- harness connector terminal 1 to Fuel Pump Control Module -J538- harness connector terminal 3 for resistance. CHECK: Fuel Delivery Unit -GX1- harness connector terminal 2 to Fuel Pump Control Module -J538- harness connector terminal 2 for resistance. CHECK: Fuel Delivery Unit -GX1- harness connector terminal 3 to Fuel Pump Control Module -J538- harness connector terminal 1 for resistance. A8 ONLY: CHECK: Fuel Delivery Unit -GX1- harness connector terminal 1 to Fuel Pump Control Module -J538- harness connector terminal 2 for resistance. CHECK: Fuel Delivery Unit -GX1- harness connector terminal 2 to Fuel Pump Control Module -J538- harness connector terminal 7 for resistance. CHECK: Fuel Delivery Unit -GX1- harness connector terminal 3 to Fuel Pump Control Module -J538- harness connector terminal 1 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were values obtained?	-- YES: GO TO: Step 6 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 6 . 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 7 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 7 .
6	REMOVE: Engine Control Module -J623-. Refer to the appropriate service information. CHECK: Fuel Pump Control Module -J538- harness connector terminal 6 to Engine Control Module -J623- wiring connector terminal T94 / 42 for resistance. A8 ONLY: CHECK: Fuel Pump Control Module -J538- harness connector terminal 4 to Engine Control Module -J623- wiring connector terminal T94 / 42 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were values obtained?	-- YES: REPLACE: Fuel Pump Control Module -J538-. Refer to the appropriate service information. GO TO: Step 7 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 7 . 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 7 Fuel Pump Control Module - J538- / Transfer Fuel Pump - G6-, CHECKING - 7 .
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