421

Possible Causes

• •Lubricating oil level is low
• •External leak
• •High ambient temperature
• •Blocked enclosure air intake
• •Coolant level below specification
• •Loose or damaged battery cable connections
• •Battery charger not connected (if equipped)
• •Battery not completely charged
• •Battery is old and does not maintain a charge

Suggested Actions

1. 1Check the oil level. Add oil, if necessary.
2. 2Inspect the engine and surrounding area for external oil leaks.
3. 3If a leak is present, contact your Cummins service representative.
4. 4Reduce loads or recirculation of discharge air to generator in elevated ambient.
5. 5Inspect for dirt, debris, or obstructions.
6. 6Remove blockage or snow/ice buildup as applicable.
7. 7Check coolant level.
8. 8Add coolant as necessary.
9. 9Inspect the battery cable connections for corrosion and loose connections. Adjust or repair if needed.
10. 10Make sure that the battery charger is connected to the AC power supply.
11. 11Make sure that the battery charger is connected correctly to the battery.

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