COVER 1527918 - Caterpillar

of an electrical component can cause the failure of other components. Also, failure of an electrical component can be caused by the failure of other components. Always attempt to correct the cause of an electrical system failure before you replace a component.Note: If you suspect that there is a problem with the Machine Security System, ensure that the machine starting system is working properly. Use the electrical system schematic to troubleshoot the starting circuit. Note: Electronic control modules seldom fail. Perform the troubleshooting procedures that are provided in the Troubleshooting, "Symptom Procedures" section of this manual, before you replace an ECM.Test procedures progress from the most likely points of failure to the least likely points of failure. The procedures normally proceed in the following order:
A component is bad.
Wiring or connectors are bad.
An electronic module is bad.Each procedure assumes the following data:
No previous troubleshooting has been performed on the system.
The system has not been altered. Assume for repair:
The batteries are fully charged and the charging system is operating properly.
Caterpillar ® Electronic Technician (Cat ® ET) is available and the technician is trained on the operation of Cat ET. See Troubleshooting, "Service Tools".During troubleshooting, inspect all connections before any component is replaced. If the 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.