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Home >> Volkswagen >> 2015 >> Golf TDI S, Standard Trans >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine & Transmission Systems (Diagnostics - CRUA - 3 Of 5) >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Reducing Agent Heater Control Module -J891-, 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 PRELIMINARY CHECK .
-- Was Complaint verified?		 -- YES:
  • GO TO: Step 2.
-- NO:
  • GATHER more information from customer about the complaint.
2 
  • IGNITION: OFF.
  • DISCONNECT: Reducing Agent Heater Control Module -J891- harness connector.
  • IGNITION: ON.
  • CHECK: Reducing Agent Heater Control Module -J891- harness connector terminals 3 and 5 to ground for voltage.
  • IGNITION: OFF.
  • SPECIFIED VALUE: Battery voltage.
-- Were Values obtained?		 -- YES:
  • GO TO: Step 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 4.
3 
  • REMOVE: Engine Control Module -J623-. Refer to appropriate service information.
  • CHECK: Reducing Agent Heater Control Module -J891- harness connector 1 to the Engine Control Module -J623- harness connector T94 / 41 for resistance.
  • CHECK: Reducing Agent Heater Control Module -J891- harness connector 2 to the Engine Control Module -J623- harness connector T94 / 31 for resistance.
  • CHECK: Reducing Agent Metering System Control Module -J880- harness connector 3 to the Engine Control Module -J623- harness connector T94 / 40 for resistance.
  • CHECK: Reducing Agent Metering System Control Module -J880- harness connector 4 to the Engine Control Module -J623- harness connector T94 / 9 for resistance.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?		 -- YES:
  • REPLACE: Reducing Agent Heater Control Module -J891-. Refer to appropriate service information.
  • 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 4.
4 
  • 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.
  • 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.
  • If all electrical connections are OK:
  • REPLACE: Engine Control Module -J623-. Refer to appropriate service information.
  • 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.
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