Leak Detection Pump (LDP) -V144-, Checking

Leak Detection Pump (LDP) -V144-, Checking

Electrical check
- Disconnect harness connector for Leak Detection Pump (LDP) -V144-.
- Connect multimeter US1119 (Fluke 83 or equivalent) between terminals -1- and -3- of LDP and check resistance.
Specified value: 640-720 ohms







- Connect multimeter US1119 (Fluke 83 or equivalent) between terminals -2- and -3- of LDP and check resistance.
Specified value: 17.5-27.5 ohms

If resistance is not OK:
- Replace leak detection pump.

Voltage supply, checking
- Disconnect harness connector for LDP -V144-.







- Connect VAG1527B LED voltage tester between connector terminal -3- (B+) and engine Ground (GND).
- Start engine and let idle.
LED must light up.

If LED does not light:
- Check fuse for LDP -V144-.
- Check wiring for open circuit between terminal -3- and fuse, according to wiring diagram.
Specified value: max. 0.5 ohms
- Check fuel pump relay. Refer "Fuel Pump Relay/Fuel Pump", Under Fuel Delivery and Air Induction" Testing and Inspection