Passenger headlight problem, relay buzz

Searched for this problem on here and found remedies referring to the stalk and melted bulb sockets. Unfirtunatley on my N reg micra these were all intact. Having searched other places on the net I found this article that described my problem exactly, the lucar connector on one of the wires on the engine fousebox had corroded away. So I thought I'd post it here for other people.

"I've got a 1996 Nissan Micra and have recently encountered a problem with the left side headlight (right hand drive car), where neither beam or dip worked (the side light was fine though). I found a lot of people on the internet who had the same problem. I've just fixed mine, so here goes!

The right hand light works directly off the light switch on the dashboard - dip, beam and side light (the left hand side light also works from the switch). The left hand headlight goes through a dim/dip unit though, allegedly due to local legislation that says that one light must continue to work if the other fails - bizarre!

Your first job is to remove the dim/dip unit - this is situated under the steering column, and is a box the size of a cigarette packet. Into this box go two cables, one that has four pins and one that has six. Without disconnecting the wires, pull the box off its mounting, and then remove the outer case using a small screwdriver to prise it off.

On the circuit board, there are two relays, which are used to switch the left hand headlight. When the side lights are switched on, the relays should click over, and when the light stalk is turned to dip, they should return. When the stalk is pushed away to obtain beam, they should click again. This is all with the ignition switch set to on (the position just before starting, or the position the key is in when the engine is running), as some of the circuits don't work when the engine is off. IF NOTHING WORKS AT THIS STAGE, then you're missing a permanent 12V. This is due to a fuse in the engine compartment.

I have seen wiring variations on the internet, such as shorting contacts on the dim/dip unit, but this is not a good idea, as you'll double the current going through the switch, and therefore burn it out.

Open the bonnet (hood) and locate the battery. In front of the battery there is a small fuse box. Open this, and locate the two 15A fuses. These run the lights, one for each side (dip and beam). Now, someone at Nissan obviously designed this at 5:29 on a Friday, because the cables that enter this fuse box are VERY taut.

To access the underside of the small fuse box, you'll need to remove the relay box that is behind it and 90 degrees to it (or between the battery and the engine). Remove the negative lead of the battery to avoid fires! You'll also need to remove the positive lead as this will allow the relay box to be lifted out along with the fuse box. There are various plastic clips and screws to remove, but with enough perseverance and swearing, they'll come out far enough to allow the fuse box to be turned over.

There'll be a red cable (with silver spots, though this could be different on other models, particularly in the US, as this car was made in the UK) that feeds the right hand side of the lower 15A fuse (this is the one that feeds the offending headlight). This is extra taut, and has probably broken off the underside of the fuse mounting. If it has, then there's your problem.

Remove the fuse, and jab a sharpish screwdriver down the left hand side of the left hand contact. This will create a hole that you can run a new wire through. Get a piece of wire about 4 inches long, making sure that it's the same (or greater) thickness as the red cable. Solder one end of this to the fuse that you just removed, on the outside edge of the fuse pin. This will now feed down into the fuse box when you replace the fuse in its holder. When you have replaced the fuse, pull the new wire through and solder it to the old wire. You may have to cut the old wire a little to allow fresh copper to solder to. Make sure that you cover the joint with thick tape (self amalgamating tape is good for this), and replace the covers on the fuse box."