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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 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 Dump.

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

Open circuit
- If there is no continuity, the circuit is open.
Repair or replace the harness.
- EVAP system leak detection pump
terminal C and PCM terminal 3V

- EVAP system leak detection pump
terminal D and PCM terminal 3Y

- EVAP system leak detection pump
terminal A and main relay terminal C

- EVAP system leak detection pump
terminal B and the body GND

Short circuit
- If there is continuity, the circuit is shorted.
Repair or replace the harness.
- EVAP system leak detection pump
terminal C and power supply

- EVAP system leak detection pump
terminal D and power supply

- EVAP system leak detection pump
terminal A and the body GND

- EVAP system leak detection pump
terminal B and power supply