Detection and analysis: because of the failure of multiple electrical functions, there is a problem of common power supply or wiring. First check the fuse box in the engine room and the fuse in the fuse box below the left instrument panel, and find the fuse fuse of No. 27 10 A in the fuse box below the left dashboard; replace the fuse, connect the ignition switch, and fuse the fuse again, indicating that the downstream power circuit of the fuse is on the short circuit of the iron lap. Look at the label on the fuse box cover and learn that the fuse provides a power supply that is controlled by the ignition switch for the skylight control module, the air conditioning control module, the body control module, and the air conditioner blower relay (because the annotation on the fuse box is sometimes incomplete, for example, a fuse is actually powered by a number of electrical appliances, but only a few of them are labeled. " Therefore, in case of fault diagnosis, the circuit diagram is necessary if necessary. Disconnect the skylight control module, the air conditioning control module and the body control module's wire connector and the air conditioner blower relay; after replacing the fuse, then restore the skylight control module, the air conditioning control module and the body control module's wire connector and the air conditioner blower relay, when installing the blower relay. Fuse and fuse. Remove the blower relay check, the relay 44 terminals, terminal 1 and terminal 3 for the relay coil control terminal, terminal 4 and terminal 5 for the blower load control terminal; measure the blower relay coil resistance, the 0.3 Omega, a short circuit fault, the normal relay coil electrical resistance should be 40 to 110 Omega. Troubleshooting: replace the 27 10A fuse in the fuse box below the blower relay and the left dashboard.