RING-BACKUP 5239717 - Caterpillar

Probable Causes
Electrical power supply
Electrical connectors
Communication adapter and/or cables
Electronic service toolRecommended Repairs
Electrical Power Supply
Check power to the ECM or the ITSM. Refer to Troubleshooting, "Electrical Power Supply".Note: If the modules are not receiving battery voltage, the modules will not communicate.Electrical Connectors
Check the following components:
Battery connections and ground to the ECM or the ITSM
Wiring harnesses and the connectors for the ECM or the ITSM
Wiring harnesses and the connectors for the ECM or the ITSM in the terminal boxRefer to Troubleshooting, "Inspecting Electrical Connectors".Communication Adapter and/or Cables
Check the condition of the fuse for the communication adapter.
Disconnect the communication adapter and the cables from the service tool connector. Then reconnect the communication adapter. If you are using the 7X-1700 Communication Adapter Gp, refer to Special Instruction, SEHS9264, "Using the 7X1700 Communication Adapter Group".If you are using the 171-4401 Communication Adapter II, refer to Manual, NEHS0758, "Communication Adapter II User's Manual".
Verify that battery voltage is present between terminal A and terminal B of the service tool connector. If the communication adapter is not receiving power, the display will be blank. Electronic Service Tool
In order to eliminate Cat ET as the problem, connect Cat ET to a different engine. If the same problem occurs with a different engine, check Cat ET and the related equipment in order to determine the cause of the problem.