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Home >> Audi >> 2015 >> A7 Quattro Premium Plus >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> 3.0L - Generic Scan Tool - Engine Code: CTUA - Transmission DTC Tables & Diagnostic Procedures >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Fuel Injectors, Checking

Fuel Injectors, Checking

Function 

The Cylinder 1, 2, 3, 4, 5, 6 Fuel Injectors -N30, N31, N32, N33, N83, N84- are controlled by the Engine Control Module -J623- and are mounted normally in the cylinder head. The fuel injectors spray high-pressure atomized fuel directly into the combustion chamber.

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: -- NO:
  • GATHER more information from customer about the complaint.
  • IGNITION: OFF.
  • DISCONNECT: Faulty Fuel Injector -- from harness connector.
  • CHECK: Faulty Fuel Injector -- component connector pins 1 and 2 for resistance.
  • SPECIFIED VALUE: 0.5 - 35 Ω (@ approx. 20° C).
-- Was Value obtained?
-- YES: -- NO:
  • REMOVE: Engine Control Module - J623-. Refer to appropriate service information.
  • CHECK: Faulty Fuel Injector -- harness connector terminal 1 to the Engine Control Module - J623- harness connector terminal. (Refer to the wiring diagram for proper terminal locations).
  • CHECK: Faulty Fuel Injector -- harness connector terminal 2 to the Engine Control Module - J623- harness connector terminal. (Refer to the wiring diagram for proper terminal locations).
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?
-- YES:
  • REPLACE: Faulty Cylinder Fuel Injector -- for a mechanical condition. Refer to appropriate repair information.
  • GO TO: Step 4 FUEL INJECTORS, CHECKING => 4 .
-- NO:
  • 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 FUEL INJECTORS, CHECKING => 4 .
  • Final Procedure 
  • Perform a road test to verify repair.
  • Do any DTC's return:
-- YES:
  • FAULT DOES RETURN:
  • REPLACE: Engine Control Module - J623-. Refer to appropriate repair information.
  • FAULT DOES NOT RETURN:
  • Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
  • Perform the diagnostic procedure for that DTC.
-- NO:
  • Repair is complete. Generate readiness code. Refer to READINESS CODE .
  • Return vehicle to Customer.