P1494

Tests 590 - 594:

Tests 595 - 596:

SYMPTOM
P1494 - LEAK DETECTION PUMP SWITCH OR MECHANICAL FAULT

WHEN MONITORED
Immediately after a cold start, with battery/ambient temperature between 40 °F - 90 °F and coolant temperature within 10 °F of battery/ambient temperature.

SET CONDITION
The state of the switch does not change when the solenoid is energized.

POSSIBLE CAUSES
- Wiring harness intermittent defect
- LDP switch sense circuit open
- LDP switch sense circuit shorted to ground
- LDP vacuum supply
- Leak detection pump defective
- PCM defective