TEST BOX 1P7219 - Caterpillar

Illustration 1 g01334596
Schematic of the Cat Data Link CircuitThis failure results in codes that are logged against an ECM that has totally lost communication with the Machine ECM. The Machine ECM cannot communicate with the Engine ECM. Note: Verify that the fuse in the circuit for the engine ECM has not blown.Test Step 1. VERIFY THE HARDWARE AND THE SOFTWARE PART NUMBERS
Verify that the following information is correct:
The part number of the software of the Machine ECM
The part number of the "Engine ECM flash software"
The part number of the Machine ECM
The part number of the Engine ECM Note: Consult the Business Unit that produces the product for the correct part numbers of the configuration software. Expected Result:All part numbers are correct. Results:
OK - All part numbers are correct. Proceed to Test Step 2.
NOT OK - All part numbers are NOT correct. The part number of the Machine ECM may be incorrect. The part number of the Engine ECM may be incorrect. The incorrect configuration software may also be installed. Repair: Replace the incorrect ECM with an ECM that has the correct part number. Flash the correct configuration software. See Troubleshooting, "Electronic Control Module - Flash Program".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.
Check the wires at the connector.
Check each wire for nicks or signs of abrasion in the insulation.
Check for moisture at the connector.
Check the connectors for dirty contacts or corroded contacts.
Check each pin and each socket of the