- Troubleshooting, "Using Caterpillar Monitoring System to Determine Service Codes"
- Troubleshooting, "Using Caterpillar Electronic Technician (ET) to Determine Service Codes"
- Parts Manual
As a guide, a simplified system schematic is included at the end of this manual. For an accurate representation of the machine that is being diagnosed, refer to the electrical system schematic in the service manual for the machine that is being serviced.
When the troubleshooting procedure instructs you to “REPAIR THE HARNESS”, use the electrical system schematic for the machine that is being serviced to trace the circuit.
Perform continuity checks at the harness connectors in order to locate harness failures.
At the connectors of the components, always check the ground circuit. Less than five ohms of resistance is required between the ground contacts of the connector and the frame ground. Excessive ground resistance that is greater than five ohms can cause incorrect diagnosing of problems.
During troubleshooting, inspect all connections before any component is replaced. If these connections are not clean and tight, permanent electrical problems or intermittent electrical problems can result. Check that the wires are pushed into the connectors completely. Make sure that the connections are tight before other tests are made.
When you perform wiring harness tests, do not puncture the wire insulation. Use test leads such as the 7X-1710 Multimeter Probe in order to troubleshoot the harness without damaging the wire insulation.
If damaged wire insulation is found during troubleshooting, repair the damage. Seal the damaged wires with 8T-0065 RTV Silicone Sealant. Cover the sealant with two layers of 1P-0810 Tape.
Failure of an electrical component can cause the failure of other components. Always attempt to correct the cause of an electrical system failure before you replace a component.
When you are removing the machine harness from the power train ECM, use the single screw in the center of the harness connector.