Help And Advice please

[AlanD]

i posted a while ago about a little electrical fire under the interior light switch, i think i have found the problem, i have just taken out the door switch on the drivers side, it operates the internal lights, open the door the lights come on, if i'm right it should have a live wire fitted to the back of it? and earth through the screw fixing?

what i have found is that the wire has been spliced and earthed
i have a dead wire, red and purple, and a black spliced into it and earthed on the body under the dash

the red and purple i think should be live from the internal switch, i have no switch fitted at the moment so the wire is dead, surley it should not be earthed ?


Thanks in advance guys

Alan

[Andrew S]

Hi Alan
It should just have a live purple wire going to the switch. I had the same query as you i the fact that if the live wire was going to earth by the switch, why wouldn't it blow a fuse? It wont, but the wire acts as an earth even though I got a reading from it on multimeter.

I am sure other that others on here can be a bit more technical about this, but for now, it should have just have one wire on the switch

Andrew

[Peter]

Alan, Andrew,

The purple and red wire should connect to the door switch. In simple electrical terms (my electrics are simple) positive from the battery is connected to the bulb the other side of the bulb is the purple and red cable so if you put a multimeter on it you will get a voltage through the bulb, connect it to earth and the bulb lights (because the bulb is the resistor it isn't a dead short and any fuse won't blow. Connecting the red and purple lead to earth should put the interior lights on. My guess would be the interior light switch on the console has failed and a previous owner has connected the red and purple to earth to enable fault finding but when they couldn't fix it they just left it connected.

Hope this helps

Peter

[AlanD]

Hi Peter/ Andrew

thanks for the input, the puddle light does not work on this door either, it lights on the passenger side when the door is open, and as you have said the switch could have been faulty, hense the meltdown of the switch and my little fire. i have replaced the burnt wire, i have a new switch too, so i think its a case of fit it and try it out, i just dont want the same to happen again if there is a problem elsewhere in the loom.

do you think i should i cut the earth wire and then fit the new switch and try it out gents?

[Peter]

Alan,

Not an easy question to answer especially as you have had an electrical fire. I would suggest you trace as much of the wiring as possible and check it looks OK, then use a multimeter and check each circult - that there is continuity from one end to the other and no leakage to earth, I'd then supply power to one circuit at a time through a link wire with a fuse. If everything checks out and works then connect it all up. You have hade a fire and someones been bodging you don't know whet else you could find - be careful.

Regards

Peter

[jleyton]

Hi Alan,

It's been said elsewhere but later cars - poss LD40000 onwards - have a different wiring arrangement to earlier models and no official wiring diagram exists for the later type. I have an unofficial one if you want to PM me with your email address or it's in the technical pages if you can find it.

The later type has just one wire to the door switches which are earthed when the door is open. The earlier type had two wires and the door switch just made or broke the circuit.

Good luck and cheers !

Julian

[AlanD]

well i put in the new switch, put everything back as it was, same again, it stared to get very hot again, found the wire at fault and now need to follow it back on the loom to find out why, mine has 2 black wires on the top, just for info. well looks like she will pay a visit to the electrician to get it sorted i think if i cant find it.


thanks to you all once again for the help


Alan

[new to this]

Alan

if you search for don kenny ( not sure if ive got name right ) but he posted a wiring diagram in colour it might help

Dave

[jleyton]

Hi Alan,

I think it was Don Kennedy but his diagrams were definitely for the earlier type of interior light wiring unfortunately - I know, I tried to use his to sort out my interior light problems !

Cheers

Julian

[AlanD]

i have looked at the wiring diagrams in the book and the one that came with the handbook, both say i should have purple wires, i have black! think i will just get an auto engineer to sort it lol

thanks guys

[brian0443]

Alan. The handbook never did cover the revised wiring for the interior lights, most easily identified by having two blacks, rather than two purples, just as you describe. You can get the information from the technical section of the main SOC website. Log in to members section,(password on page 3 of magazine). Then go to Members Area, then Technical section,then the 'If time is of the essence' hint for searchable database, and select page 215. Everything you or an auto-electrician will need is on that page. If you can't find it PM your e-mail and I'll scan and forward it to you.

For clarification its page 215 of the PDF index page 209 in the original document.
Brian

[Peter]

More and more confusion, I always thought the wires were purple (with tracers) and you either had two with a switch or one with a switch that completed the circuit to earth. Check what type of switch is fitted to both doors, do they have one or two connectors? Also if it earths the connecting wire it should be the one wire system. My car was made in 1974 (LD33952 body number T33964) and it has the single wire system with door switches that earth...


Peter

[brian0443]

Peter,
apart from the black earth wires, and the all purple live feed, all the other wires in both systems are as you said, purple with tracers. To allow for the single wire system to the earthed door post switches, the wiring at the console switch had to be altered. So on the early type, two purple live wires to the top position. The later ones have the blacks in this position. Interesting that yours, with a body number 863 before the 'accepted' (guesstimated?) change over point, has the later system.

So as with many other things 'Stag'; Its what you have got and not what the book says you should have
Brian

[AlanD]

well i have the 2 black wires, and the switch is earthed through the screw

i think i will just get the auto electrician to have a look at it, i dont want to buy another switch at 35 pounds, and i dont want the loom burnt out either

thanks for all your help lads, another thing i have learnt, my wiring is BL patchwork !!

manufacture date was 11/76 if this helps anyone

thanks again

Alan

[jleyton]

Hi Alan,

Yours was made about the same time as mine and has the same switch/wiring arrangement.

If you take it to an electrician, I'd provide him with the wiring diagram that I emailed you.

Cheers

Julian