a 2009 models Shanghai GM Buick Excelle sedan, users complained that the car can not be started recently frequent fault, then he completely unable to start, I stand by the towed trailer maintenance. According to users to reflect, sometimes suddenly turn off during normal driving the car, sometimes the remote control does not work, there is no law. The car is often the case can not be burning fuse from time to time before the advent of the car, and to other repair stations checked several times, the service personnel replace the fuse of the vehicle will return to normal, but has not found the cause. Now appeared in the replacement of the fuse plug would be immediately destroyed, completely unable to start the engine of the phenomenon.
FIG 1
FIG. 2
Firstly, the author found frequent damage of two melt wire, they are anti-theft system fuse F10 and the F11 fuse hazard warning lights (FIG. 1). After the author Symptom car was verified. Test was found, the starter is not operating the vehicle start to open after the ignition switch gear is not displayed on the instrument panel, while a plurality of electrical system (air conditioner blower, lifter, headlamps, turn signals and remote control, etc.) are can not work normally. After I found the car ignition switch relay correlation circuit diagram (FIG. 2), each of the test system used to test the lamp does not work, such as air conditioner blower, and the relay lifter headlights, the fuse is not found in the supply voltage after the ignition switch is opened.
a circuit diagram of careful observation apparent above, each of the fuse by a controlled ignition relay, the relay control ground by a keyless entry receiver, a fuse F11 by the hazard warning lights provide an ignition power supply (FIG. 3), it will not be a result of faulty ignition switch ignition relay can not pull it? In order to verify the author’s judgment, I use the lamp according to FIG. 3 again, carefully examined each of the ignition switch gear power. Been found that the actual test, respectively, when the ignition switch is at ACC, ON and ST positions, the wire harness after the ignition switch can supply is normal, the ignition switch is not described problem. After determining the ignition switch is normally located in the engine compartment I decided to check the ignition relay. When using the test lamp test it found that the constant power supply relay 30 with an electrical terminal, the relay coil terminal No. 86 has an electrical power supply, but that does not pull the relay, a control of the relay contactThe line barrier.
Figure 3
where the need to remind the maintenance personnel, in ldquo; ignition power rdquo; control, the new Excelle and Excelle old control The method is completely different. Old Excelle uses a direct control of the ground, as long as the ignition switch is open, it will pull power to the relay coil, and the ignition coil is connected directly to ground control relay (FIG. 4); Excelle is grounded by the new remote controller the receiver (RCDLR) control, when the remote receiver to a proper unlocking signal may be turned on after the ignition relay. The vehicle power supply both electrical power supply relay is activated. Accordingly, the new and old Excelle car theft, the ignition start control and power control of the vehicle body is completely different appliances. Old Excelle after the vehicle theft is triggered, the alarm call and hazard warning lights flashing, but as long as a valid key blocker is still the car; new Excelle If an alarm condition, the body can not turn on electrical appliances and starter relay power, of course, not the car.
Figure 4
of the above, in view of the ignition relay control ground is lost, the car is I suspect because the number F10 fuse burning caused by the ignition relay can not pull, causing the starter can not function, body electrical failure and a series of failures. So what causes burning fuse F10 is it? Remove center armrest find Remote Keyless station receiver checks its associated wiring harness, and there is no short circuit is discovered. After replacing the burned fuse the F10, the remote testing normal function, start the engine of the vehicle can now be found that smooth start. But when the author steering lamp, the fuse box fires again found to provide power to turn the lamp No. burned fuse F22. Pressing the hazard switch, Discovery F11 15A of the hazard warning also will fuse burning. At this point I did not replace the fuse again, I decided to check the instrument panel line. Suddenly smelled minor pills only to discover, after careful examination, found flasher relay station below the left side of the instrument overheating burning. The author then burning turn signal relay (FIG. 5) is removed, while the hazard warning lights relay removed, again under the rated capacity replacement F22, F11 fuse No.. After again function tests found that when pressing the lock button on the remote control, there is no problem; when pressing the unlock button remote control, remote control door lock receiver number burning fuse F10 again.
Figure 5
Figure 6
Remote locking is no problem, but it will unlock the remote burning the fuse will not be a short circuit remote Keyless unlock signal to the receiver of the central locking control unit it? Remote Keyless so I found a circuit diagram associated with the receiver (FIG. 6), remove the lock located in the control side of the right front pillar A door control unit, the receiver checks Remote Keyless unlock the door between the central line, the line is not short circuit place. A fuse connected again, but without the use of a remote control door lock control switch and a gate driver side door provide control door locking, unlocking the fuse is not damaged, but why the remote control using the remote control remote locking and unlocking a normal burning fuse it? Contact to turn lights the fuse, I suddenly thought, will not open the bonnet when the vehicle is not locked into the security state, so only when locking control central locking control without turn signal blinking, no matter what the state will be unlocked flashing turn signal control it? So I covered good engine cover is closed the doors, pressing the lock button on the remote control again, remote control door lock receiver number really burned fuse F10 again, it appears that the author’s judgment is correct. Why can manipulate the remote control number F10 fuse will burn it? Could it be that the remote control door lock receiver is an internal malfunction caused by the use of the remote control or turn lights the fuse burned down when the turn signal? So I decided to replace the keyless entry receiver. After replacing the receiver and Remote Keyless reprogramming reloaded No. F10 fuse test, the fault remains the same, the point of failure should turn signal line.
Figure 7
So I find a circuit diagram of a vehicle turn signal (FIG. 7) can be seen on each side of the car 3 around the steering lights, instrument panel as well as two turn indicators, whether it is a problem which line it? Because flasher relay is burning, the door can only use the remote control to turn lights flashing verify point of failure. I Remove Remote Keyless receiver harness connector, a circuit diagram of the control terminal 13 to pick out the right turn control the lamp, the door is closedWell, repeatedly press the remote control lock, unlock key, found the remote control door lock receiver No. F10 fuse did not burn again. Thereafter, the author will in turn controls pin 26 of the left turn signal lamp is turned off, the right turn lamp refitted terminal 13, the remote control operation is found again, No. F10 fuse burning immediately. The results show the detection problem right turn lamp line. So I circuit diagram, remove the right front passenger-side seat inspection line, no abnormal. After harness terminals are disconnected right turn lamp C401, C303 and C361, found on the right side mirror when the harness terminal disconnection fault disappears. Is rearview mirror steering failure caused by light? It brought a new rearview mirror assembly from parts library, installed after the test found fault disappears. You may determine that the fault lies on the right side exterior mirror turn signal.
again after communication with the user that the original right side of the car had an accident, we do not go to a regular service station for repair, but close to home to find the nearest roadside shop replaced a non-original on the right exterior mirrors, only after a series of failures has been found in the car. I removed the fault mirror, after the lens is removed, the wire harness actually found blinker is sandwiched between the fixing bolt. About 3 000 km of failure to appear more obvious symptoms may be why the car accident driving it? It should be judged at the time of the new spray paint solid, relatively thick, the mirror mounting bolts and the door did not short-circuit. When certain mileage of the vehicle, because the bumps, shaking and friction, so that the door mirror fixing bolt starts short, when the user uses the remote control or the turn signal steering circuit to ground short circuit will cause the lamp is started, whereby steering and burned fuse keyless entry receiver.
Finally, after replacing the right exterior rear view mirror assembly, troubleshooting.
Summary: In fact, because the root cause is the turn signal circuit shorted to ground, but after a series of logic control caused unimaginable results. Rpm lines caused by short circuit turning lamps, hazard warning, keyless entry receiver burned like a fuse, a fuse and said control unit is precisely controlling the ignition power supply relay and the ground portion, so that any problems will arise a condition causing ignition relay can not pull. When the ignition relay is not pulls in, the most direct consequence of the starter relay is no power while the engine fuel injection, ignition and the vehicleBody electrical systems, and many have lost power, resulting in a failure of the car. Failure by the maintenance of the car, I suggest that the majority of maintenance personnel in the maintenance of system failure must grasp the principle, the same need to accurately grasp the different technical characteristics of different models of the same car, grabbed detail, prioritize, rely on strict logic, and ultimately determine the cause.
(Bo)