17 replies to this topic

[humpy76]

Hi all,

I have been experiencing an issue for some time now and need to get some idea as to why or whats going on, I put angel eye headlights on my minster in July. Since then I have had two new light switches which keep melting around a copper conector located on the back of the switch (middle one to be precise)....it takes a couple of months for the plastic to slowly give way, however, I'm lost with what to do.... I could put the old headlights back in (which would be a waste of £50 (or there abouts), or keep buying switches at £7, and wait until a fire erupts or try and fathom what I need to do to stop my headlight switch from melting and stop being caught out when driving in the dark and lights just deciding to turn off.

Scatching my head yet again........

Regards,

Mark

[Bungle]

what size bulbs have you got in them ? :erm:

[Guess-Works.com]

sounds like too much wattage in the bulbs matey, and you havn't done anything silly like wire a set of spot lights in have you ?? :saywhat:

[bousfield19]

what you need to do is fit a better relay to the lights that should sort your problem out i had the same problem on my car and i fitted a relay to it (because it didnt have one as it was an old car) and this sorted all of the problems out

[humpy76]

Thanks for the comments!
I installed bulbs that were supplied and as documented in the instructions.... I dont have spot lights wired in on the car yet, but will try and put a relay in the line...... any clues as to where or how to do this would be gratefully received!?

Thanks again...

Mark

[dklawson]

"Standard" headlamps (if there is such a thing) typically have a rating of something like 55W/65W for low/high. A lot of aftermarket bulbs (halogens in particular) will have high-beams upwards of 100W. This is a significant increase in the current the wiring is carrying. The suggestion above to add a relay (or two) to operate the headlamps is your best solution.

As mentioned, early cars didn't have relays at all and it's cheap insurance to add the relays. They protect the wiring in the harness, the dash switch, and the dimmer switch by reducing the "in-car" wiring to carrying only a few milli-Amps instead of several amps.

[rob mini]

the relay will sort it. mine did this and on about the 4th switch i decided to catch fire so i had to do something to sort it and quickly! that time i put the new switch and relay in and was fine for all the rest of the time i owned it.

rob

[Madmax]

my car decided to set on fire due to the headlamp switch, if anyone on the nurburgring run can remember...


this is a dangerous thing, as you could have a serious fire on your hands



fit a relay fast

[jam2005]

I've just uprated my headlamps to the mini trailers ons. Should I fit a relay and if so which one and how?

Cheers, Jam2005 :grin:

[pikey7]

the "pucker" way of doing it is to wire up two relays. one for main, and one for dip. the existing lighting circuits should be used for switching on the relays, and then run a bit of HD wire to the relay from the alternator +, and then onto the headlights. It's a job I will do on my car, however, i've not yet looked into the best place to nick the signal.

An easier option, would be to place a relay at the switch. Use the switch to switch on the relay, and then use the existing headlamp wiring to carry the curent to the lights. I would tell you the colours to connect, but my haynes is STILL not here for me to look at. maybe someone else can point you in that direction (or I can when it comes through.....)

[humpy76]

Thats a right touch..... I will be getting on the case asap.... relay race so to speak.

Again thanks for the information, I will be getting this done as a priority based on the fire stories !

Mark

[topcat]

Why isnt the light switch fused!? I noticed this on the wiring diagram, its ridiculous. Mine melted out and the main feed to the switch shorted with an ignition lead so my cd player started switching itself on! Had to re-wire it all and its been ok for a couple of weeks so fingers crossed!

[Dan]

Well a fuse wouldn't have helped anyway. The plastic rocker switches used in Mini's are rated at 16A continuous and the standard headlamp load is far to close to this, it's about 14.7A. So when things start to break down in the system (corrosion in the connectors among other things increases the current drawn by the ciruit) and you start to change things you get really close to the switches rating and it starts to melt. So even if you had a fuse it would need to be rated higher than the switch can handle or it would blow all the time. A better switch or relays are the only answer.

The bulbs that come with most halogen lamp kits (or even the standard halogen lamps fitted to late Mini's) only have 55/60w lamps as that's the legal maximum on the road here. You can buy higher wattage lamps but they are marked for off road use only. Don't forget DK that in most countries replaceable bulb halogen lamps aren't treated as black magic by the authorities and have been standard fitment for ages, you don't see 'Halogen lighting' listed as a major feature of a car over here.

Fit your relays in the engine bay and use the original lighting circuits to switch them, taking the power from the starter solenoid rather than the alternator. The switching in the car makes it much more complicated to fit them inside and you would need to run the power feeds through the bulkhead and back. If you have a car built after 88 then the dim dip system effectively means that the dipped beam is already running through a relay so you don't need to worry about that. I believe that the main beam was never run through a relay as standard.

[ImagoX]

Fit your relays in the engine bay and use the original lighting circuits to switch them, taking the power from the starter solenoid rather than the alternator. The switching in the car makes it much more complicated to fit them inside and you would need to run the power feeds through the bulkhead and back. If you have a car built after 88 then the dim dip system effectively means that the dipped beam is already running through a relay so you don't need to worry about that. I believe that the main beam was never run through a relay as standard.

Sorry to necro-post, but I have a question on this.

I'm in the US and I purchased a set of replacement lamps with 100W halogens to put in my UK-spec 1992 Mini Sprite. I know that if I just swap the lights without changing the wiring that I'll melt the switch, so I'll have to run a relay, using the OE headlight circuit as the trigger voltage - I get that.

What I don't understand is this comment on the "dim dip system". Does the above statement mean that all I need to run is a relay for the HIGH BEAMS and that the other beam is already on a relay? Note that here in the US, we call the normal headlights the "main beams" and the brighter beams as the "high beams", so I might be confused on terminology. Are "dip beams" the normal headlights and the "main beams" what WE call the "high beams"?

Thanks!

PS - in case it helps, this is the unit I have that I'm needing to install:

http://www.gbcarpart...d=Lamp7Headlamp

Edited by ImagoX, 02 January 2008 - 03:25 PM.

[DaveRob]

Are "dip beams" the normal headlights and the "main beams" what WE call the "high beams"?

Above is correct.

Re 100W bulbs..... 100W bulbs at 12Vdc is 8.3 amps PER LIGHT..... you will need at least 20 amp relays and Id suggest 1 for dipped and one for mains..at least..... also check your alternator capacity with 200W and 17amps in 2 bulbs remember you have to power all the other lights and sounds. or you will just flatten the battery

DaveRob