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Home >> Volkswagen >> 2018 >> Passat R-Line >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine System (Diagnostic Procedures - DDSA, DDSB) >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Fuel Tank Leak Detection Control Module - J909-, Checking >> Test Procedure
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Test Procedure

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.
  • REMOVE: Evaporative Canister.
  • Plug or Cap off the Fuel Tank Leak Detection Control Module -J909- port going to the vent filter.
  • CONNECT: Hand vacuum pump to the Fuel Tank Leak Detection Control Module -J909- CAN port and apply 0.700 bar and see if the vacuum holds.
-- Did the vacuum hold?
-- YES:
  • GO TO: Step 3.
-- NO:
  • REPLACE: Fuel Tank Leak Detection Control Module -J909-.
  • GO TO: Step 5.
  • IGNITION: OFF.
  • DISCONNECT: Fuel Tank Leak Detection Control Module -J909- harness connector.
  • IGNITION: ON.
  • CHECK: Fuel Tank Leak Detection Control Module -J909- harness connector terminal 4 to ground for voltage.
  • IGNITION: OFF.
  • SPECIFIED VALUE: Battery voltage.
-- Was Value 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 5.
  • REMOVE: Engine/Motor Control Module -J623-.
  • CHECK: Fuel Tank Leak Detection Control Module -J909- harness connector terminal 1 to the Engine/Motor Control Module -J623- harness connector T91 / 37 for resistance.
  • CHECK: Fuel Tank Leak Detection Control Module -J909- harness connector terminal 2 to the Engine/Motor Control Module -J623- harness connector T91 / 21 for resistance.
  • CHECK: Fuel Tank Leak Detection Control Module -J909- harness connector terminal 3 to the Engine/Motor Control Module -J623- harness connector T105 / 20 for resistance.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?
-- YES:
  • REPLACE: Fuel Tank Leak Detection Control Module -J909-.
  • GO TO: Step 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.
  • 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.