SHOE-TRACK 1910921 - Caterpillar

Illustration 1 g01197858
Schematic for the Cat Data LinkThis diagnostic code is recorded when the implement ECM is unable to communicate with the engine ECM.The possible causes of this diagnostic code are listed:
The data link wire between the implement ECM and the engine ECM has failed.System Response:The machine response is listed:
Implement valve calibrations will not work due to unavailable engine speed input.
The pilot on/off solenoid valve will shut off when all the levers are in the HOLD position.Note: Ensure that the diagnostic code is active.Test Step 1. CHECK THE COMPATIBILITY OF THE SOFTWARE.
For the correct software part numbers, refer to the Electronics Groups in the parts manual for the machine that is being serviced.Expected Result:The software is compatible.Results:
YES - The software is compatible. Proceed to Test Step 2.
NO - The software is not compatible.Repair: Flash the proper software to the appropriate ECM. Cycle the key switch in order to initialize the new software. Ensure that the diagnostic code is no longer active. If this does not resolve the problem, proceed to Test Step 2.Test Step 2. CHECK THE +BATTERY CIRCUIT AT THE ECM CONNECTORS.
Turn the disconnect switch to the OFF position.
Turn the key start switch to the OFF position.
Disconnect connector J1 from the ECM.
Turn the disconnect switch and the key start switch to the ON position.
At the connector J1, measure the voltage between all possible sources of positive voltage to all possible sources of ground.Expected Result:The voltage measures 18 DCV to 35 DCV.Results:
YES - The voltage measures 18 DCV to 35 DCV. The voltage is correct. Proceed to Test Step 3.
NO - The voltage measures less than 18 DCV.Repair: Ensure that there is a proper ground. Also, check the circuit breakers. If the ground is proper, the power circuit has failed. Repair the power circuit or replace the power circuit. If this does not resolve the problem, proceed to Test Step 4.Test Step 3. CHECK FOR A DATA LINK CIRCUIT SHORT TO GROUND.
Turn the disconnect switch to the OFF position.
Turn the key start switch to the OFF position.
Inspect the harness connectors that are related to the Cat Data Link circuits. Ensure that the connector contacts are clean and that the connectors are tight. If necessary, repair the connectors or replace the connectors.
Disconnect the harness from all modules.
Measure the resistance between the Cat Data Link connectors and all possible sources of ground. The Cat Data Link connectors are J1-8 and J1-9.Expected Result:The resistance is greater than 5000 Ohms for each measurement.Results:
YES - The resistance is greater than 5000 Ohms for each measurement. The machine is correct. Proceed to Test Step 4.
NO - The resistance is less than 5000 Ohms for each measurement.Repair: The short is between the circuit with the resistance that is less than 5000 Ohms and contact 9 (wire 945-BR) and contact 8 (wire 944-OR). Repair the harness or replace the harness. Stop.Test Step 4. CHECK FOR A DATA LINK CIRCUIT SHORT TO POSITIVE VOLTAGE.
The disconnect switch and the key start switch remain in the OFF position.
All the modules