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P1494 Leak Detection Pump Switch or Mechanical Fault

SYMPTOM
P-1494 LEAK DETECTION PUMP SW OR MECHANICAL 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 switch does not change when the solenoid is energized.

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