P1494

Tests 1157 - 1160:

Tests 1161 - 1164:

Test 1165:

SYMPTOM
P-1494 LEAK DETECTION PUMP SW OR MECH FAULT

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

SET CONDITION
The state of the leak detection pump switch is not in its expected state at key-on (engine not running). Or, following an engine start, a change in switch state is not seen when the LDP solenoid is energized to pull the pump diaphragm to its "up" position

POSSIBLE CAUSES
- Fused ignition switch output circuit open
- LDP pressure switch circuit shorted to ground
- Leak detection pump switch sense circuit open
- Leak detection pump defective
- LDP wiring harness intermittent defect
- LDP wiring harness observable def
- LDP vacuum hose leaking or obstructed
- Powertrain control module defective