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Leak Detection Pump: Testing and Inspection

EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK DETECTION PUMP INSPECTION

Airflow Inspection

NOTE: Perform the following test only when directed

1. Disconnect the negative battery cable.




2. Remove the EVAP system leak detection pump. (See EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM COMPONENT REMOVAL/INSTALLATION.)
3. Blow air into port A and verify that there is airflow from port B.
- If not as specified, replace the EVAP system leak detection pump.

4. Blow air into port B and verify that there is airflow from port A.
- If not as specified, replace the EVAP system leak detection pump.
- If as specified, perform the following "Resistance Inspection".

Resistance Inspection

NOTE: Perform the following procedure only when directed.

1. Disconnect the negative battery cable.







2. Inspect resistance of the EVAP system leak detection pump.
- If not as specified, replace the EVAP system leak detection pump.
- If as specified, carry out the "Circuit Open/Short Inspection".

Circuit Open/Short Inspection
1. Disconnect the PCM connector, (See PCM REMOVAL/INSTALLATION.)




2. Inspect the following wiring harnesses for open or short circuit (continuity check).

Open circuit
- If there is no continuity, there is an open circuit. Repair or replace the wiring harness.
- EVAP system leak detection pump terminal C (harness-side) and PCM terminal 3V
- EVAP system leak detection pump terminal D (harness-side) and PCM terminal 3Y
- EVAP system leak detection pump terminal A (harness-side) and main relay terminal C (harness-side)
- EVAP system leak detection pump terminal B (harness-side) and the body GND

Short circuit
- If there is continuity, there is a short circuit. Repair or replace the wiring harness.
- EVAP system leak detection pump terminal C (harness-side) and power supply
- EVAP system leak detection pump terminal D (harness-side) and power supply
- EVAP system leak detection pump terminal A (harness-side) and the body GND
- EVAP system leak detection pump terminal B (harness-side) and power supply