HEAD A.-CYL. 8B8870 - Caterpillar

The Electronic Control Module (ECM) detects an unexpected loss of a continuous J1939 speed signal on the J1939 data link.
The expected continuous speed signal has never been received on the J1939 data link.TroubleshootingCheck the configuration of the ECM. If the ECM for the engine has been incorrectly configured to expect a continuous J1939 speed signal, remove "Continuous" for the J1939 speed signal on the main "J1939" screen on the electronic service tool.Test Step 1.
Perform the following diagnostic procedure
Use the OEM information to determine the machine ECM that provides the continuous speed signal.
Refer to the troubleshooting procedures from the OEM to diagnose the faulty speed signalResults:
OK - STOP