RADIO GP-COMMUNICATION 5157080 - Caterpillar

the 2461 diagnostic codes.
Remove the jumper wire.Results:
A 2461-5 diagnostic code was active before installing the jumper. A 2461-6 diagnostic code is active when the jumper is installed - The fault is in the CEM harness.Repair: Repair the faulty wiring or replace the faulty wiring.Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.STOP
A 2461-5 diagnostic code is still active with the jumper installed. - Reconnect the 40-pin connector. Proceed to Test Step 5.Test Step 5. Create a Short Circuit at the 31-Pin Connector
Turn the keyswitch to the OFF position.
Disconnect the 31-pin connector.
Fabricate a jumper wire that is 150 mm (6 inch) long.
Install the wire between pin 21 and pin 22 on the 31-pin connector on the harness between the engine and the CEM.
Turn the keyswitch to the ON position. Wait for 10 seconds. Check for active diagnostic codes on the electronic service tool.Note: While the 31-pin connector is disconnected, diagnostic codes for the other components