Leak Detection Pump, Checking
Leak Detection Pump, Checking
Special tools, testers and auxiliary items required
- Multimeter.
- Wiring diagram.
Test requirements
- The Leak Detection Pump (LDP) V144 Engine Electronics Fuse S282 OK.
- The ignition switched off.
NOTE: The voltage for the Leak Detection Pump (LDP) -V144- is supplied via the Fuel Pump (FP) Relay J17.
Procedure
- Remove the left rear wheel housing liner.
- Disconnect the Leak Detection Pump (LDP) V144 electrical harness connector.
Checking internal resistance
- Using a Multimeter , check the Leak Detection Pump (LDP) V144 for resistance as follows:
Leak Detection Pump (LDP) Specified value
V144 electrical harness
connector terminals
1 + 3 640 to 720 Ohms
2 + 3 15 to 17 Ohms
If any of the specifications were not obtained:
- Replace the Leak Detection Pump (LDP) -V144-.
If the specified values were obtained:
Checking voltage supply
- Using a Multimeter , check the Leak Detection Pump (LDP) -V144- electrical harness connector terminal 3 to Ground (GND) for voltage.
Leak Detection Pump (LDP) Measure to
-V144- electrical harness
connector terminal
3 Engine Ground (GND)
- Operate the starter briefly.
Specified value: battery voltage.
- Switch the ignition off.
If the specified value was not obtained:
- Check the wiring for a short circuit to Ground (GND) or an open circuit.
- Check the electrical harness connector for damage, corrosion, lose or broken terminals.
- If necessary, repair the faulty wiring connection.
It the specification was obtained.
Checking wiring
If the manufacturers test box is being used. Perform the following step.
- Install the test box.
If the manufacturers test box is not being used. Perform the following step.
- Remove the Motronic Engine Control Module (ECM) J623.
- Using a Multimeter , check the Leak Detection Pump (LDP) -V144- electrical harness connector terminals to the Motronic Engine Control Module (ECM) J623 electrical harness connector T121 terminals for an open circuit.
Leak Detection Pump (LDP) Motronic Engine Control Module
V144- electrical connector (ECM) J623 electrical connector T121
terminals terminals or test box socket
1 80
2 25
Specified value: 1.5 Ohms
If the specification is not obtained:
- Check the wiring for a short circuit to Battery positive (+) or an open circuit.
- Check the electrical harness connector for damage, corrosion, lose or broken terminals.
- If necessary, repair the wiring connection.
If no malfunction is found in wiring:
- Replace the Motronic Engine Control Module (ECM) J623.
Assembly is performed in the reverse order of the removal, note the following:
- Install the right rear wheel housing liner.
Final procedures
After repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory. Diagnostic Mode 03 - Read DTC Memory
2. If necessary, erase the DTC memory. Diagnostic Mode 04 - Erase DTC Memory
3. If the DTC memory was erased, generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes