Activating Leak Detection Pump (LDP) V144 :

• Press → button.

Indicated on display

Output Diagnostic Test Mode -> Leak Detection Pump (LDP) V144

The fuel system Leak Detection Pump (LDP) V144 must click until the output DTM is terminated by pressing the → button.

If the diagnostic pump does not click:

• Remove right rear wheel housing liner. → 66 EXTERIOR EQUIPMENT

• Disconnect 3-pin harness connector - arrow  - from Leak Detection Pump (LDP) V144.

• Using adapter cables from VW 1594 , connect voltage tester VAG 1527B to disconnected harness connector terminals - 2  - and - 3  -.LED must flash (bright/darker)

If LED flashes:

• Proceed with output DTM until completed.
• Switch ignition off.
• Replace fuel supply system Leak Detection Pump (LDP) V144. → 20 - FUEL SUPPLY
• Check DTC memory. If necessary, repair any malfunctions and erase DTC memory → Diagnostic Trouble Code (DTC) memory, checking and erasing (scan tool functions 02 and 05)  .

• Display readiness code → Readiness code (function 15), displaying  . If DTC memory has been erased, the readiness code must be generated again → Readiness code (function 15), generating  .

If LED does not flash:

• Proceed with output DTM until completed.
• Switch ignition off.
• Remove wiper arms and plenum chamber cover. → 92 WINDSHIELD WIPER & WASHER SYSTEM

• Connect Test box VAG 1598/31 to control module wiring harness. The engine control module is not connected by this action.

• Check wiring for open circuit between test box and 3-pin harness connector using wiring diagram. Terminal - 1  - + socket 80. Terminal - 2  - + socket 25. Wire resistance: max. 1.5 Ω
• Additionally, check wire for short circuit to battery positive (B+) and Ground. Specification: ∞ Ω

• Using wiring diagram, check wire between terminal 3 of relay plate and Fuel Pump (FP) relay J17 for open circuit. Wire resistance: max. 1.5 Ω

If no wiring malfunction is detected:

• Replace Motronic ECM J220 → Engine Control Module (ECM), replacing  .