In the workshop this week we were presented with a 2007 Ford Focus suffering from an array of electrical problems including interior lights, glove box light and boot lights not working.
After checking the fuses and finding a blown one, we replaced it and it blew again indicating a short circuit. we then consulted a wiring diagram to establish what consumers were on the circuit and disconnected them.
Even with the consumers disconnected the fuse had continuity to earth. This meant it had to have a wiring fault. to find this fault, unfortunately, we had to remove front seats, some of the centre console and glove box to trace the wire from the BCM (body control module) eventually we found the wire had rubbed through and shorted out at the rear of the vehicle.
After inspecting the other wires in that location and making sure there was no damage to any of the others we then repaired the broken wire and refitted the interior.