VALVE 9J1988 - Caterpillar

Illustration 1 g02578036
Schematic of the Cat Data Link
This diagnostic code is recorded when the Engine ECM is not sending parameters to the Implement ECM at the proper rate. The update rate for parameters that are generated by the Engine ECM is not correct.The possible causes of this diagnostic code are listed:
The data link circuit has an open circuit.
The data link circuit is shorted to battery ground.
The Engine ECM is not operating properly.
The software for the Engine ECM has been erased.
The Engine ECM has the wrong software.System Response:The machine response is listed:
When the engine is being started, the implements will not be locked out.Note: Ensure that CID 0590 FMI 09 is inactive. If a diagnostic code for the data link is active, correct this diagnostic code. If this diagnostic code is inactive, then check the Engine ECM for proper operation and active diagnostic codes.Test Step 1. VERIFY THE HARDWARE AND THE SOFTWARE PART NUMBERS
Verify that the following information is correct:
The part number of the flash software for the Implement ECM
The part number of the flash software for the Engine ECM
The part number of the Implement ECM
The part number of the Engine ECM Note: Consult your Caterpillar Dealer for the correct part numbers of the flash software.Expected Result:All of the part numbers are correct.Results:
OK - All of the part numbers are correct. Proceed to Test Step 2.
NOT OK - All of the part numbers are not correct. Repair: The installed Implement ECM or the Engine ECM have the wrong part number or the incorrect flash software is installed. Replace the incorrect Implement ECM or the Engine ECM with a module that has the correct part number. Flash the correct software. See the Testing and Adjusting, "Electronic Control Module (ECM) - Flash Programming" section for additional information.STOPTest Step 2. INSPECT THE HARNESS CONNECTIONS
Turn the disconnect switch to the OFF position.
Inspect all harness connections that are related to the Cat Data Link. Make sure that the connectors are clean and tight.
Check the connectors for proper mating. Ensure that all the seals are present and in place.
Check the harness for signs of damage or abrasion.
Check the wires at the connector. Ensure that the wires are secured tightly into the connector. Take care not to pull the wire out of the connector.
Check the exposed wires at the connectors for nicks or signs of abrasion.
Check for moisture inside the connector.
Check the connectors for dirty contacts or corroded contacts.
Check each pin and each socket of the machine harness connectors. Ensure that the contacts are properly installed. The contacts should mate correctly when the two pieces of the connector are placed together. Expected Result:The machine harness connectors are tight and free of corrosion. Results:
OK - The machine harness connectors are tight and free of corrosion. Proceed to Test Step 3.
NOT OK - The machine harness connectors are in need of repair.Repair: Repair the machine harness or replace the machine harness. STOPTest Step 3. CHECK FOR SHORTS TO GROUND
The disconnect switch remains in the OFF position.
Disconnect the machine