With Generic Scan Tool

Leak Detection Pump (LDP), Checking

Recommended special tools and equipment
- V.A.G1526 multimeter or V.A.G1715 multimeter
- V.A.G1594 connector test kit
- Wiring diagram

Requirements







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

Test sequence
- Right rear wheelhousing liner, removing:







- Disconnect 3-pin connector of Leak detection pump (LDP) -V144- (arrow).







- Measure resistance between terminals 1 + 3 of diagnostic pump.
Specified value: 640 to 720 Ohms
- Measure resistance between terminals 2 + 3 of diagnostic pump.
Specified value: 12.5 to 19.5 Ohms

If specified values are not obtained:
- Replace Leak detection pump (LDP) -V144-.
- 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. Monitors, Trips, Drive Cycles and Readiness Codes

If specified values are obtained:
- Connect test box to control module wiring harness. Test Box, Connecting For Wiring Test







- Check wires between test box and 3-pin connector for open circuits according to wiring diagram.

Terminal 1 + socket 80
Terminal 2 + socket 25

Wire resistance: max: 1.5 Ohms

- Check wires for short circuit to each other, to vehicle Ground (GND) and to B+.
Specified value: Infinite Ohms

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

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