Operation CHARM: Car repair manuals for everyone.

Leak Detection Pump: Testing and Inspection







Leak Detection Pump Checking

Special tools, testers and auxiliary items required

• Multimeter.

• EVAP Smoke Machine

• Wiring diagram.

Test requirements

• The Leak Detection Pump (LDP) (V144) fuse 15 in fuse panel B is OK.

• The ignition switched Off.

Test procedure

- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check

Start diagnosis

- Remove the right rear wheel housing liner. Refer to the Repair Information.

- 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:






If any of the specified values were Not obtained:

- Replace the Leak Detection Pump (LDP) (-V144-). Refer to the Repair Information.

If the specified values were obtained:

Checking voltage supply

• The voltage for the Leak Detection Pump (LDP) (-V144-) is supplied via fuse 8 in Fuse Panel B.

- Check the Leak Detection Pump (LDP) (-V144-) for voltage.

- Using a multimeter, check the Leak Detection Pump (LDP) (-V144-)electrical harness connector terminal 4 for voltage and connect the negative lead to engine ground.

- Turn the ignition switch ON.

Specified value: Battery voltage.

- Switch the ignition Off.

If the specified value was Not obtained:

- Remove fuse 8 in Fuse Panel B. Using a multimeter, check the Leak Detection Pump (LDP) (-V144-) wiring from terminal 4 to fuse 8.

Specified value: 1.0 ohms max.

If the specified value was Not obtained:

- Check the wiring for high resistance, short to ground or an open circuit.

- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

- If necessary, repair the faulty wiring connection.

If the specified voltage was obtained:

Checking wiring

- Remove the Engine Control Module (ECM) (J623). Refer to the Repair Information.

- Using a multimeter, check the Leak Detection Pump (LDP) (-V144-) electrical connector terminals to Engine Control Module (ECM) (J623) electrical connector terminals for an open circuit or high resistance.






Specified value: 1.0 ohms max.

If the specified value was Not obtained:

- Check the wiring for high resistance or an open circuit.

- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

- If necessary, repair the faulty wiring connection.

If no malfunction is found in wiring, the LDP resistance and the voltage supply were OK:

- Replace the Engine Control Module (ECM) (J623). Refer to the Repair Information.

Assembly is performed in the reverse order of the removal, note the following:

- Install the right rear wheel housing liner. Refer to the Repair Information.

Final procedures

After repair work, the following work steps must be performed in the mentioned sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.