* Air Leak: This is the most common cause. A leak somewhere in the system (air lines, air bags, compressor seals) causes a pressure drop. The pump kicks on to try and maintain the desired pressure, even when the vehicle is off. The leak could be slow, only triggering the pump intermittently or after a delay.
* Faulty Air Suspension Pressure Sensor: This sensor monitors the air pressure in the system. If it's malfunctioning and reporting low pressure, the pump will attempt to compensate, even with the key off.
* Faulty Air Suspension Control Module (or relay): The control module manages the entire air suspension system. A fault within it could cause the pump to run continuously or sporadically, even without the key on. A related issue could be a faulty relay that's stuck closed.
* Stuck Air Suspension Compressor Relay: Similar to the module, a stuck relay will keep power to the compressor, regardless of the key position.
* Wiring Issues: Short circuits or damaged wiring can also lead to the pump running continuously. This is less likely but possible.
Troubleshooting Steps (in order of likelihood):
1. Listen Carefully: Try to pinpoint where the air leak might be. You might hear hissing near the air bags (under the vehicle) or along the air lines. Inspect all visible components for damage or cracks.
2. Check the Air Bags (Visually): Carefully examine the air bags for any visible tears or damage. These are often located near the wheels and under the vehicle.
3. Pressure Check (If Possible): If you have the tools and knowledge, a pressure check of the air suspension system can help identify a leak.
4. Scan for Diagnostic Trouble Codes (DTCs): Use an OBD-II scanner to check for any error codes related to the air suspension system. These codes can pinpoint the faulty component.
5. Professional Diagnosis: If you can't identify the problem, taking your Navigator to a mechanic specializing in air suspension systems is recommended. They have the tools and expertise to diagnose the issue accurately.
Ignoring this problem will eventually drain your battery and could lead to more significant air suspension issues down the line. Address it promptly.
