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Home >> Volkswagen >> 2021 >> Jetta R-Line, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Generic Scan Tool (Transmission DTC Tables & Diagnostic Procedures) [DKFA] >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Engine Component Power Supply Relay - J757-, CHECKING
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Engine Component Power Supply Relay - J757-, CHECKING

General Description 

The following procedure is used to diagnose the Engine Component Power Supply Relay -J757- and the power supply voltage that is provided to the Ignition Coils --.

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: Engine Component Power Supply Relay -J757- from the Fuse box in the engine compartment.
  • IGNITION: ON.
  • CHECK: Engine Component Power Supply Relay -J757- harness connector terminals 111 and 113 to ground for voltage.
  • IGNITION: OFF.
  • SPECIFIED VALUE: Battery voltage.
-- Were Values obtained?
-- YES: -- NO:
  • CONNECT: Jumper wire, between the Engine Component Power Supply Relay -J757- socket terminals 113 and 115.
  • DISCONNECT: Ignition Coil 1, 2, 3, 4 With Power Output Stage -N70, N127, N291, N292- harness connectors.
  • IGNITION: ON.
  • CHECK: Ignition Coil 1, 2, 3, 4 With Power Output Stage -N70, N127, N291, N292- harness connector terminals 4 to ground for voltage.
  • IGNITION: OFF.
  • SPECIFIED VALUE: Battery voltage.
-- Were Values obtained?
-- YES: -- NO:
  • REMOVE: Jumper wire, between the Engine Component Power Supply Relay -J757- socket terminals 113 and 115.
  • REMOVE: Engine/Motor Control Module -J623-. Refer to appropriate service information.
  • CHECK: Engine Component Power Supply Relay -J757- socket terminal 112 to the Engine/Motor Control Module -J623- harness connector T91 / 8 for resistance.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Was Value obtained?
-- YES: -- NO:
  • 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-. 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 CODES .
  • 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.