hi a have a disco 300tdi auto with a lot of electrical problams ie hore. back wiper. courtesy light all not working . alarm thinks a door is open when i lock the car .i have replaced the MFU with a new one with no luke anyone help
door: Push the switch in the sill in hard and jiggle it a bit. see if it works. if not check the connectors have not come of the switch. if it is connected, pull the switch out, check it with a multimeter beep function, if working, its your loom, if not replace switch and try again. you can always short the connections together to see if it works too.
Horn: pop bonnet and find horn, check connections, see if wires have fallen out. If wires ok: hook bulb up to horn connections and press horn. if bulb comes on, horn wiring ok, horn knackered, replace horn.