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Home >> Audi >> 2014 >> S7 >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control Systems >> 4.0L - Generic Scan Tool - Engine Code(S): CEUC & CRDB (Transmission DTC Table & Diagnostic Procedures) >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Motronic Engine Control Module Power Supply Relay -J271 -, 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 concern.
2
  • DISCONNECT: Motronic Engine Control Module Power Supply Relay -J271-
  • CONNECT: jumper wire, Motronic Engine Control Module Power Supply Relay -J271- socket terminal 5 to 3.
  • IGNITION: ON
  • SPECIFIED VALUE: Battery voltage at fuses for engine management. (Refer to wiring schematic for component and fuse location).
  • IGNITION: OFF
-- Was value obtained?
-- YES:
  • GO TO: Step 4
-- NO:
  • GO TO: Step 3
3
  • IGNITION: ON
  • CHECK: Motronic Engine Control Module Power Supply Relay -J271- connector terminals 2 to ground for voltage
  • CHECK: Motronic Engine Control Module Power Supply Relay -J271- connector terminals 3 to ground for voltage
  • SPECIFIED VALUE: Battery voltage
  • IGNITION: OFF
-- Was value obtained?
-- YES:
  • GO TO: Step 4
-- NO:
  • CHECK: wiring for open, high resistance, short or connector for damage, corrosion, loose or broken terminals
  • REPAIR: faulty wiring or connector
  • REPLACE: any open fuses
  • GO TO: Step 5
4
  • REMOVE: Engine Control Module -J623-. Refer to the appropriate repair information.
  • CHECK: Motronic Engine Control Module Power Supply Relay -J271- connector terminal 1 to Engine Control Module -J623- wiring connector terminal T91 / 87 for resistance
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω)
-- Was value obtained?
-- YES:
  • REPLACE: Motronic Engine Control Module Power Supply Relay -J271-. Refer to the appropriate repair information.
  • PERFORM: Road Test to verify repair.
  • FAULT DOES NOT RETURN:
  • FAULT DOES RETURN: no malfunction is detected in the wiring.
  • REPLACE: Engine Control Module -J623-. Refer to proper repair information for removal and replace procedures.
  • GO TO: Step 5
-- NO:
  • PERFORM: Visual Inspection of wiring and component
  • CHECK: wiring for open, high resistance, short or connector for damage, corrosion, loose or broken terminals
  • REPAIR: faulty wiring or connector
  • GO TO: Step 5
5
  • Final Procedure
  • Perform a road test to verify repair.
  • Do any DTC's return:
-- YES: -- NO:
  • Repair is complete, Generate readiness code. Refer to READINESS CODES .
  • Return vehicle to Customer