If EPC warning lamp illuminates continuously

Fig 1: Identifying Test Box V.A.G 1598/31 Connect To Control Module Wiring Harness

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Connect Adapter cable, 121 pin VAG 1598/31 to control module wiring. Do not connect engine control module.
• Use wiring diagram to check wiring between jack 48 of test box and instrument panel for a short circuit to ground.

If the wiring is OK:

• Replace engine control module: Refer to 24 MULTIPORT FUEL INJECTION (MFI)