With Generic Scan Tool

Check Leak Detection Pump (LDP)

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram

Test requirements
- The respective fuses of Leak detection pump (LDP) -V144- must be OK:
- Ignition switched off.

Test sequence
- Remove right front wheel
- Remove front right wheelhousing liner.
- Disconnect connector of Leak detection pump (LDP) -V144- (arrow).







- Connect multimeter for resistance measurement as follows.

Leak detection pump (LDP) -V144- Specified value
Terminal
1 + 3 640 ... 720 Ohm
2 + 3 15 ... 17 Ohm

If specified values are not obtained:
- Replace Leak detection pump (LDP) -V144-, item 4
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Readiness Code, Generating

If specified values are obtained:







- Connect VAG1598/31 test box to connectors of wiring harness. Ground (GND) clip (arrow) at test box must be clipped to battery minus. Do not connect Engine Control Module (ECM).







- Check the following wire connection for open circuit and short circuit to Ground (GND) and B+:

Electrical Harness connector VAG1598/31 test box
Terminal Socket
2 25
1 80

- Check wire between 3-pin connector terminal 3 and the Fuel Pump (FP) Relay -J17- for open circuit according to wiring diagram.
Wire resistance: max: 1.5 Ohm

If no malfunctions are found in wires:
- Replace Motronic Engine Control Module (ECM) -J220-.