Test Procedure

WARNING: This page is about a different car, the 2018 Audi A3 Quattro, 2017 Audi A3 Quattro, 2016 Audi A3 Quattro, 2016 Audi A3, and 2015 Audi A3 Quattro. However, it is still accessible from the selected car via links, so may be relevant.

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. -- NO: GATHER more Information from customer about the complaint.
2	IGNITION: ON. LISTEN: Fuel Delivery Unit -GX1- should be heard running for 2 s. IGNITION: OFF. SPECIFIED VALUE: Transfer Fuel Pump ON for 2 s. -- 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. -- NO: GO TO: Step 3.
3	DISCONNECT: Fuel Pump Control Module. -J538- IGNITION: ON. CHECK: Fuel Pump Control Module -J538- harness connector terminals 3 to 4 for voltage. CHECK: Fuel Pump Control Module -J538- harness connector terminal 4 to battery voltage for voltage. CHECK: Fuel Pump Control Module -J538- harness connector terminal 3 to ground for voltage. IGNITION: OFF. SPECIFIED VALUE: Battery Voltage. -- Were Values obtained?	-- YES: 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 7.
4	RECONNECT: Fuel Pump Control Module -J538-. DISCONNECT: Fuel Delivery Unit -GX1-. CRANK: Engine. For TT vehicles: CHECK: Fuel Delivery Unit -GX1- harness connector terminals 1 to 2 for voltage while engine is cranking. For A3 vehicles: CHECK: Fuel Delivery Unit -GX1- harness connector terminals 1 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 appropriate Service Information. GO TO: Step 7. -- NO: GO TO: Step 5.
5	DISCONNECT: Fuel Pump Control Module -J538-. CHECK: Fuel Delivery Unit -GX1- harness connector terminal 1 to the Fuel Pump Control Module -J538- harness connector terminal 1 for resistance. For TT vehicles: CHECK: Fuel Delivery Unit -GX1- harness connector terminal 2 to the Fuel Pump Control Module -J538- harness connector terminal 2 for resistance. For A3 vehicles: CHECK: Fuel Delivery Unit -GX1- harness connector terminal 5 to the Fuel Pump Control Module -J538- harness connector terminal 2 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Were Values obtained?	-- YES: GO TO: Step 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.
6	REMOVE: Engine Control Module -J623-. Refer to appropriate Service Information. CHECK: Fuel Pump Control Module -J538- harness connector terminal 5 to Engine Control Module -J623- wiring connector T91 / 9 for resistance. SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω). -- Was Value obtained?	-- YES: REPLACE: Fuel Pump Control Module -J538-. Refer to appropriate Service Information. GO TO: Step 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.
7	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. If all electrical connections are OK: REPLACE: Engine 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.