4 replies to this topic

[The Otter]

Model: 1992
Year: City E
Description of problem (please be as in depth as possible):

Was driving along today, and thought I could smell burning. I just put it down to it being a Mini, and always have some sort of odd noise or smell to accompany me on the journey. However, after about 20-30 minutes of average driving (bit of town traffic, A roads, dual carriageway, etc.) smoke started billowing from behind the dash. My first though was something along the lines of "HOLY ****" and luckily the road I was driving on had big wide pavements on either side, so I pulled in as quickly as I could and turned the car off, opened both doors to let the smoke out and then got out myself, fearing the worst. Thankfully after about 20-30 seconds the smoke had pretty much disappeared, so I ventured in to find out the problem. After moving the dash out of the way and taking the stereo out, I found it was a wire on the harness to the stereo had completely melted and all that was left was the copper wire, which is now as brittle as anything and falling to pieces. After I got home and had a proper look I found that it was the earth wire, the one that used to be black before it all melted away...

It was bucketing down whilst I was driving, I had the sat nav plugged in, the wipers going, the lights on, and obviously the stereo on with my iPod plugged in through an auxiliary input, if any of this makes any difference.

I've got some pictures of what it looks like now:

This was the block connector that went in to another block connector, which then went in to the stereo. The wire from the other connector to the stereo didn't melt away like this, but it is a bit melted/warped at the ends.







This is the connector on the back of the actual stereo, as you can see the top right is where it got pretty hot.



This is where the earth wire went to. The wire melted and split in half, and it's the ring connector on the very bottom of this photo. I don't know if having five things earthed on the same point has anything to do with this problem?



Close up of the ring connector.



This was the last burn mark on the red and yellow wires, about half way along until they connect up to the loom under the steering column.



If anyone could tell me what happened here, and how to stop it from happening again, I would very much appreciate it! Obviously I'm going to need some new bits to replace the damaged part of the stereo harness, but no point getting anything just to have it melt again.

I think I was lucky that it wasn't any worse...

Cheers guys, Sven.

[The Otter]

Just to add, the car starting misfiring during the rain, which it has done before, so I wasn't too worried. I dried it out, it helped a bit but not much, and now later in the day when it is completely dry (I know because I've made sure it's dried thoroughly) it's still misfiring just as bad. The car is still just about drivable, but it's not pleasant to drive at all. I have an Aldon electronic ignition set up as well, the one that replaces the points, so am thinking these two problems may be linked some how?

[JonnyBMX]

okay so the wire heating up.. basically.. could be due to it shorting out and creating a short circuit... causing it to heat up.. this could have been caused by a small cut/rip in the wire protection.

do you have a mutli meter? just replace the earth cable and ensure that there are no exposed areas that will be able short out on the chassis or anything. otherwise im not sure what the problem could be and it may be wise to get some who knows what they are talking about to have a look at the whole lot including the stereo..?

[MiniLuke]

I would have thought a fuse should have blown. Is the live wire to the radio correctly wired to the correct side of the fuse block?

I assume your stereo stopped working too. I suspect something within the head unit has failed. Perhaps an inline fuse in the live wire might be the way to go. If it blows as soon as you reconnect and turn on the radio, then the head unit is to blame.

What is the yellow wire for?

[The Otter]

Just to let you guys know, the melted earth wire was down to my stupidity. I hadn't properly insulated the live wires going into the three auxiliary dials in the middle of my dash, and as I had the lights on it effectively shorted out and sent all the current through the metal casing of the stereo and down the earth wire, therefore melting it. That's the current theory anyway

Oh, and the misfire was actually the car running on three cylinders When I'd taken the dizzy cap off to dry it, I must have damaged it and created a crack, which meant the spark didn't go to the metal point in the cap properly.

All sorted now though! New dizzy cap, a new bit of wiring, and plenty of insulation tape to stop this happening again. Just goes to show what careless wiring can do... embarrasing on my part

Oh, and I believe the yellow wire is for the stereo memory, to keep the clock right and keep it on the right radio station, etc.

Cheers for the replies guys, Sven.