HUB 5270741 - Caterpillar

Figure 1.8 Improper Harness Routing At ECM and Customer ConnectorsRouting of the harness should ensure the connector seal is not stressed because the harness wiring curvature is too close to the connector. This applies to routing of wiring near the engine Valve Cover, Harness Connector, all engine mounted components as well as the J3/P3 Customer Connector and all display connectors.The previous diagram illustrates the problem if the harness curvature is too close to the connector. When this occurs the connector seal is stretched away from the wire, providing an opening for moisture entry. The wire should exit perpendicular to the connector with 25 mm (1.0 inch) of straight length before curving as necessary for routing. The harness bundle should have a bend radius greater than twice the harness diameter.
Figure 1.9 Harness Routing At ECM and Customer ConnectorsTwisted pair wiring should be used for the ATA Data Link and the CAT Data Link. There should be a minimum of three twist per 25.4 mm (1.00 in) within the harness. All twisted pair wires should not be twisted within an inch of the connector to avoid seal stress.The acceptable range for the wire insulation outside diameter is 2.54 to 3.43 mm (0.100 to 0.135 in) for the J3/P3 40-Pin Customer Connector and 2.54 to 3.81 mm (0.100 to 0.150 in) for the HD Connectors. DT Connectors wire insulation diameter is 2.4 to 3.68 mm (0.088 to 0.145 in).Caterpillar requires all ring terminals and splices connected to the Customer Connector be sealed using Raychem ES2000 adhesive lined heat shrink sleeve (Caterpillar 1E2358 Specification) or equivalent.