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Fuel Tank Leak Detection Control Module -J909 -, Checking

General Description

The system can test the evaporative system integrity by using natural vacuum after the engine is shut off. The Engine Control Module -J623- monitors the ability of the system to maintain vacuum through signals sent from the Fuel Tank Pressure Sensor -G400- and the Fuel Tank Leak Detection Control Module -J909-. If the vacuum remains for a specified period of time, then there are no evaporative leaks, and a PASS is reported by the Engine Control Module -J623-. If there is a leak, the system either will not achieve a vacuum, or a vacuum cannot be maintained. Usually a fault can only be detected after a cold start.

Special tools and workshop equipment required 

Test requirements

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.
  • IGNITION: OFF.
  • REMOVE: Evaporative Canister. Refer to appropriate Service Information.
  • Plug or Cap off the Fuel Tank Leak Detection Control Module -J909 - hose going to the vent filter.
  • CONNECT: Hand vacuum pump to the Fuel Tank Leak Detection Control Module -J909 - 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 -. Refer to appropriate Service Information.
  • GO TO: Step 5.
  • 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 Control Module - J623-. Refer to appropriate Service Information.
  • DISCONNECT: Fuel Tank Leak Detection Control Module -J909 -. Refer to appropriate Service Information.
  • CHECK: Fuel Tank Leak Detection Control Module -J909 - harness connector terminal 2 to the Engine Control Module - J623- harness connector T105 / 26 for resistance.
  • CHECK: Fuel Tank Leak Detection Control Module -J909 - harness connector terminal 3 to the Engine Control Module - J623- harness connector T105 / 53 for resistance.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?
-- YES:
  • TIP: The Fuel Tank Leak Detection Control Module -J909 - may fail under loaded operation; please swap a known good Fuel Tank Leak Detection Control Module -J909 - prior to continuing to the next step.
  • 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 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.