BLOCK-COUPLING 1453349 - Caterpillar

System Operation Description:Note: This procedure checks for an open circuit or for a short circuit in the Cat Data Link. If you are experiencing problems with communications between the Caterpillar Electronic Technician (ET) and the Electronic Control Module (ECM), refer to troubleshooting without a diagnostic code Troubleshooting, "Electronic Service Tool Will Not Communicate with ECM" before you use this procedure.The Cat Data Link is the standard data link that is used by the ECM to communicate with Cat ET. The ECM communicates with Cat ET in order to share status information and diagnostic information. Cat ET can also be used to configure the ECM parameters. This information will not be available if communication fails between the ECM and Cat ET.
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Schematic for the Cat Data Link
Test Step 1. Inspect the Electrical Connectors and the Wiring
Remove the electrical power from the ECM.
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Typical engine view
(1) J1/P1 ECM connectors
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Typical engine view
(2) P61 customer connector
(3) P63 service tool connector
Thoroughly inspect connectors (1), (2), and (3). Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".
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P1 terminals that are associated with the Cat Data Link
(P1-8) Cat Data Link +
(P1-9) Cat Data Link −
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J61 and P61 terminals that are associated with the Cat Data Link
(6) Cat Data Link −
(7) Cat Data Link +
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the Cat Data Link.
Check the allen head screw on each ECM connector for the proper torque. Also, check the allen head screw on the customer connector for the proper torque. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values. Expected Result:All connectors, pins, and sockets are completely inserted and coupled. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The harness and the connectors appear to be OK. Proceed to Test Step 2.
Not OK - The connectors and/or the wiring are not OK.Repair: Repair the connectors and/or the wiring.