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EVAP Leak Detection Pump, Checking

Special tools and workshop equipment required 

Test requirements 

Test procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK 

Start diagnosis 

-- Remove the right rear wheel housing liner.

Checking voltage/resistance 

-- Disconnect the Leak Detection Pump (LDP) --V144-- electrical harness connector.

-- Turn the ignition On.

-- Using a multimeter, check the Leak Detection Pump (LDP) --V144-- terminal 1 to ground for voltage.

Specified value: Near 3.52 V

-- Using a multimeter, check the Leak Detection Pump (LDP) --V144-- terminal 2 to ground for voltage.

Specified value: Near 3.52 V

-- Using a multimeter, check the Leak Detection Pump (LDP) --V144-- terminal 3 to ground for voltage.

Specified value: Near 3.52 V

-- Using a multimeter, check the Leak Detection Pump (LDP) --V144-- terminal 4 to ground for voltage.

Specified value: Battery voltage

If all of the specified values were obtained: 

-- Replace the Leak Detection Pump (LDP) --V144--.

If any of the specified values were Not obtained: 

Checking wiring 

-- Remove the Engine Control Module (ECM) -J623-.

-- 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.

Leak Detection Pump (LDP) --V144-- electrical harness connector terminal: Engine Control Module (ECM) -J623- electrical connector T94 terminal:
1 31
2 72
3 50
4 Fuse (Refer to Wiring Diagrams for fuse ID.)

Specified value: 1.5 Ω max.

If the specified value was Not obtained: 

-- Check the wiring for high resistance, short or 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 and the terminal 1, 2 or 3 voltage check was Not OK: 

-- Replace the 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 the repair work, the following work steps must be performed in the following sequence:

  1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
  2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
  3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .