Jump to content
Forum software update now live Read more... ×
carld

Light switch

Recommended Posts

Hi guys, on the way to Spa, my light switch/stalk spontaneously caught fire in the outside lane of the M1, has anyone had any experience with the replacements on the market, I understand that you have to modify the mounting?

 

Thanks in advance Carl

Share this post


Link to post
Share on other sites

Hi

 

Firstly my sympathies this must have been a dramatic event and the cure is equally as painful in my experience.

My experience started with I believe the radio cassette continuous feed removed itself from the DIN plug and earthed. I had taken this feed from the horn and this burnt out a considerable amount of the wiring loom in the steering column.

 

So long winter was spent stripping the steering and dashboard to repair the damage. In doing so the original light switch (LU35783) and indicator switch could not be saved so Moss supplied me with replacements.

 

Not relevant to your issues but the indicator wiring was incorrect on the replacement and the return lobs where not long enough to self correct- pretty poor product. Issues that I didn't pick up until to far into putting things back together so now operate currently with workarounds - if I did this again I would go for a good original ( second hand) and refurbish it - probably cheaper

 

Any way to your light switch, the replacement was fitted and functioned fine until last weekend, 18 months from the repair. With the sunny weather, MoT due decided to check the beast over - now I cant remember when I last drove the TR at night summer motoring etc so checking with headlights on main beam I turned the steering wheel and the car shorted. I could not repeat this with side lights on .

 

Off with Bezel and had a gander - Well ***** me if the main light feed ( blue & white wire) attachment point to the switch protrudes towards the steering column, such that either the 'slack' in the column bushes allowed the column or the indicator return - I could really work out which- was causing an earth which, if left, would have wiped out the loom with associated fire I experienced originally.

 

Being a sad squirrel I had kept the original burnt out light switch when I look at this the main beam wire feed it is connect on the body side of the switch ie is orientated away from the steering column therefore cant cause my problem.

 

If you look at the part photo advertising the replacement part on Moss website, as I did, you will see the main light feed projecting to the steering column once fitted - this may be your issue if you were driving with head lights on and have recently replaced the light switch.

 

Hope this helps - also the dip switch I bought at the same time appeared that flimsy I refurbished the original and got on with it! some pretty poor and potential dangerous products here

 

All the best.

 

Nonothing

 

Share this post


Link to post
Share on other sites

sorry to read this nonothing, yes it was a bit of a change your pants moment, it appears to be the original switch, clear hooters i think, lights were not on at the time, but i may have used the main beam flash.

 

Now need to find the time o see how far down the wiring the damage has been done, hoping its only as far as the tails from the switch and not the main loom

 

Cheers Carl

Share this post


Link to post
Share on other sites

i am also thinking it may be wise to put a relay in

Share this post


Link to post
Share on other sites

Carl had you changed to brighter bulbs in recent months ?

there was a spate of this in the 90s when some changed to 100w bulbs.

Share this post


Link to post
Share on other sites

Hi Roy, no the same as I have had for the 12 years of ownership

Share this post


Link to post
Share on other sites

If it's been apart my money would be on the black painted metal "guard" that covers the wiring from the steering wheel where it goes through the column mounts as the culprit, catching one of the wires and damaging the insulation. It's simply barely big enough.

It's a bad design and even if you are careful the wires can get caught.

 

The replacement light switches are poor the rivets not being tight and in my recent experience fouling the flasher contacts.

 

I would advocate fusing your lighting circuit and putting in relays - this way you can protect the wiring to the switch with a low current fuse and minimise the load on the lamp switch contacts.

Share this post


Link to post
Share on other sites

Hi Folks,

be careful with fuses. These do have a habit of failing for no apparent reason.

The last thing you want is the light to go out when best needed.

 

Use a relay between switch and bulbs

Ensure that the wiring is fitted very well and not getting crimped.

 

For that bundle under the cover on the steering column I removed that plastic sleeve and fitted thin wall cable wherever possiible. to save/gain space.

If using relays then a thinner wire could be used.

 

Roger

Share this post


Link to post
Share on other sites

The thin wall (modern) cables is a great idea.

I fitted the original wiring, and the protective metal guard.

I have fused relais included, there is one fuse per filament, this eliminates the risk of suddenly driving without lights, should a fuse blow.

Regards,

Waldi

Share this post


Link to post
Share on other sites

Way back in the 1900s ( 1980? ) I fried the light switch via the high/low beam foot switch - pressed it and the lights went off. That switch was repaired by fabricating a new brass contact which was thicker by the amount the plastic had melted away, compensating therefore. Beware...

 

I use a repro in my show car, which is never driven at night - so really not at all. My driver has original wiring and switches all round, 50 years old and fully operational. The previous owner greased all the loom connections with dielectric grease 22 years ago - maybe that has helped.

 

Cheers,

Tom

Share this post


Link to post
Share on other sites

Thanks guys, new switch has arrived and hoping to sort out on saturday including fusing and relaying.

 

Cheers Carl

Share this post


Link to post
Share on other sites

Out of interest guys where have you mounted your relays, thanks in advance

 

Cheers Carl

Share this post


Link to post
Share on other sites

Carl,

Mine are under the dash, driver side (which is LHS for me).

Invisible, unless you sit on your knees.

It is very tight there, so in a next life I would install them in front of rhe A-post. Make sure your wires are long enough.

Waldi

Share this post


Link to post
Share on other sites

Stupid question, but how does the metal sleeve come off? Further investigation shows that the main blue power wire that goes to the foot switch is fried also, pondering now as to whether I put a normal rocker switch under the dash for the lights and just fit the stalk for show. The amount of room on that sleeve is ridiculous and poorly designed

Share this post


Link to post
Share on other sites

It has a clamp behind the dash at the end of the tray but the tray also goes through the column bracket that is bolted to the back of the dash, take the speedo and rev counter out as it makes it much easier to see whats going on.

Stuart.

Share this post


Link to post
Share on other sites

Well, I have bypassed the cooked wiring and rewired another switch under the dash for now. It looks as if it's dash out to get to the ridiculous channel with the cover to do the proper job, which will have to wait until winter

Share this post


Link to post
Share on other sites

Thanks Stuart, going to do in the winter months, hope all is well mate

 

Cheers Carl

Share this post


Link to post
Share on other sites

In the early 80s i could only obtain new from MOSS an american switch which had WIPE written on it.Which i still have somewhere . Found replacement at a parts sale which i am sure came from a mini,maybe i had to change the surround to black but the same switch although 2 speed.

Edited by roy53

Share this post


Link to post
Share on other sites

I was never happy with all the permanently or ignition live wires passing through the metal column harness cover. In fact I recall that the first owner of my car had a short from the overdrive feed at this point before the car was three years old! When I removed my light switch for repair years ago I took the precaution of wrapping the metal cover with lots of insulating tape just in case. Removing the column switches and associated wiring is a bit of a fiddle but perfectly doable if you remove the speedo and tacho as Stuart advises. No need to take the dash out. In my case (6'4") access is also helped by removing the driver's seat and steering wheel.

 

Tim

Share this post


Link to post
Share on other sites

Personally I would fit a latching relay and get rid of the foot dipswitch. (already wired relays into the headlamp circuits )

 

Although after spending all day on the 4a doing this last Sunday only to discover that the new relay was duff, the supposedly 6A diode (a diode is needed if you want to retain the headlamp flash) and then to compound it a duff earth lead from the latching relay saw me in need of a lot of beer and wine on Sunday evening.

 

All sorted now. Diodes going back to the vendor who can't believe that a 50v 6A diode could possibly fail on the fraction of an amp needed to trigger the main beam relay. Well Old Chap they did (x3) and the measured current was a fraction of an amp!

 

The wiring for this is in TRaction 227.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×