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OPERATION AND MAINTENANCE MANUAL FOR FOTON VIEW SERIES LIGHT BUS
·232· Chapter 11 Structure, Application and Service of Electrical Devices & Instrument 11.1 Electrical System Overview The rated voltage for electrical devices on BJ6536 series of light bus is 12V. Single wire system is adopted for the circuit of electrical devicess, with negative grounding. The circuit for the complete vehicle is composed of three major harnesses. Front panel harness is wired inside the cab; body harness is located inside engine compartment; and chassis harness is arranged inside the frame. The insertings of front panel instrument harness and chassis harness must be dismantled before cab is to be disassembled. Most electrical fittings and harnesses are connected with plug connector except very few of them jointed with bolts, which is beneficial to inspection and maintenance. It is not allowed to randomly change the positions of plug during use, so as to ensure the reliability and safety of the circuit. All the circuits are fitted with fuses. The fusible link is designed to protect the vehicle circuit, it breaks when circuit current becomes high. Fusible link should be replaced after a fault has been removd. It is not allowed to use other metal conductor as fuse. Refer to the diagram for connection of vehicle electrical devices (See the electrical wiring diagram attached to this book). 11.2 Fuse Box Fuse box integrates multiple electrical connections in one place to facilitate easy check and service on vehicle electrical devices. Refer to the indication diagram and parameters on fuse box cover to locate the wiring of each device and perform service. Use of other electrical fittings beyond specfication is not allowed.. 11.3 Troubleshooting If faults are noticed during driving and sevice check, operator can pinpoint fault locations according to electrical diagram, performs service or replacement. Never change connector location at random or connect wrong wire. Fault check starts with the most convenient place, and places where faults frequently happen such as bulb/fuse, and plug-in connectors.. 11.3.1 Gasoline Engine Failure Startup Use elementary diagram to remove gasoline engine fault. Here are some typical faults during startup: (1) While ignition switch is set to START, cannot hear starter electro-meganetic switch clicking and starter rolling.. (2) Electo-magenetic clicking is heard, but starter does not run. (3) Starter begins to roll, but engine does not start up. (4) Hear continious clicking sound. Analysis: 1. No starter switch clicks when ignition switch is set to “START”. Check if battery is connected. If battery is connected, test ignition switch and start relay power outputs. Repair or replace ignition switch or relay if there is power, otherwise test starter power connector. If the connector is hot, it indicates that starter switch attracts coil. Repair the starter. 2. When ignition switch is set to “Start”, starter electro-magnetic switch clicks but starter does not run. This indicates there is no continuity at starter due to burntout or dirty main contacts. Adjust starter switch travel and |