An annual production of FAW Pentium 2.3L sedan, equipped with L3 engine, matching FS5A-EL automatic transmission, mileage of 8000km, the user reflects the open ignition switch, the dashboard without any display, and the reverse impact of serious.
    First check the fuse of the instrument cluster and find that the 15A fuse of the instrument has been blown. Check the circuit diagram that the fuse by the ignition switch power supply, the current into the instrument panel, the instrument inside and then to the TNS relay power supply and instrumentation alarm power. Maintenance personnel suspected that the internal short circuit caused by fuse fuse, then decided to replace the fuse test. The results of the engine after the fuse does not appear fusing phenomenon, and the instrument shows normal. But in view of the fuse fuse that there must be short-circuit line situation, it must find the point of failure. Just prepare the road test into the reverse gear, the instrument immediately did not show, and the impact of a reverse gear, indicating that the instrument power supply circuit and the road. Check the instrument fuse to find that the fuse blows again. According to the circuit diagram, the reversing lamp is also powered by the instrument 15A fuse. So check the reversing light line, found in the left side of the reversing light harness has been clearly pierced traces. Touch the side of the negative line with the hand found that there is a very small wire pierced the wiring harness, resulting in reverse light line short circuit, making the transmission of a fuselage fuse will fuse, the instrument power supply interruption, showing no.
    After the repair of the damaged line, the test troubleshooting.