Cummins

DS21

UnclassifiedCooling

What This Code Means

Network Error LED (DS21) turns on red within 10 seconds; Communications have failed; NODE 'OK' LED (DS22) does not flash; Device does not attempt to bind to a genset

Possible Causes

  • •J1 data cable disconnected from the engine interface board
  • •Twisted pair cable disconnected
  • •Node Address (S2) is set to 0 (zero)

Suggested Actions

  1. 1Reconnect the twisted pair cable and confirm that DS21 turns off within ten seconds
  2. 2Ensure each device on the network has a unique address (change Node Address (S2) to a non-zero address)

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