P1494

Tests 1 - 3:

Tests 4 - 8:

Tests 9 - 11:

SYMPTOM
P1494 LEAK DETECT PUMP SWITCH OR MECHANICAL FAULT

WHEN MONITORED
Immediately after a cold start, with battery/ambient temperature between 40 °F and 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
- Wiring harness
- LDP switch sense circuit open
- LDP switch sense circuit shorted to ground
- Leak detection pump
- Vacuum hose
- Powertrain control module