200 Side lights out....fuse keeps blowing

[Philpott]

I noticed i had a number plate light out today tryed changing it and i think ive blown something.

I now have both number plate lights out and nsf/r side lights out to ive checked the fuses next to the steering wheel and they are all fine.

Checked the hidden fuse box in the bonnet and found the sidelight fuse for nsf/r side had blown so replaced and tested......blew again.....anyone help me?

 

[Twisty]

If you are blowing fuses like that it indicates that somewhere your positive wire is shorting to the earth/chassis. I am surprised it is doing it on a new car, usually it is because the insultation has worn through.

 

[Philpott]

Think was due to me replacing plate lights with leds started the problem

 

[mattg]

I had a similar thing on my R27 when I put LEDs into the number plate lights - turned out that the contacts on one of the bulb holders were touching so I bought new one! Might be worth disconnecting both the number plate bulb holders and see if the lights still short out. Hope that helps.

 

[Philpott]

So mattg the two metal arms (bulb holders) in plate lights are NOT suppose to be touching?? take it these lights then run of same circuit as passagers sidelights explains why all not working?

 

[mattg]

From memory - no they shouldn't. The two metal parts are separate parts which slot through to make up the plug on the other end. I don't think they should be touching anywhere. Trouble is that once you've removed the original bulb the connections will never be in the same position as I found, bending them back just made it worse!

The circuits are all strangely linked. My 197 is different again as I only lost lights on one side of the car when I tripped out the rear number plate bulb - very strange but there you go. It's even more peculiar that the fuse box should be underneath the acoustic valve, took some finding first time round.

 

[Twisty]

Thats it, one of those arm's is +ve and the other is -ve. If they touch then in effect you are bypassing the LED and shorting your battery to the chassis (through the fuse).

So I'd probably make a spacer up using some plastic (in the past I have used bits of biro pens cut to size) or PVC tape to to it from shorting.