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VeeTee

Member Since: 06 Mar 2011
Location: Somewhere
Posts: 1512

The melting light switch is a common failure, caused by poor design. All current is going through the switch contacts, after some time the switch will fail due to melting of the plastic which is holding the copper contacts. This *will* happen sooner (if driving much with lights on or towing) or later.

The solution is the use relays to switch the lights, then only the small current to operate the relais flows through the switch.
You can make this from ordinary relais but you can also buy complete sets with connectors on, plug and play

, like I bought such a complete set in Sweden:

Cheers, Vincent
1959 Polynorm 1/4 Ton Trailer, Olive Drab Green (sold)
1970 M416 Military Trailer (Camping Trailer Conversion), Epsom Green (sold)
1975 Series III 88 V6, Light Green (sadly sold)
1996 Defender 110 CSW 300 Tdi, Epsom Green (sold)
2000 Freelander 1 TD4 3-drs, Silver (sold)
2006 Freelander 1 TD4 5-drs Facelift Automatic, Tonga Green (sold)

MySite

Last edited by VeeTee on 21st Sep 2013 3:25pm. Edited 1 time in total

18th Nov 2012 11:51pm

Inigo

Member Since: 13 Nov 2011
Location: Kent
Posts: 625

2012 Defender 110 Puma 2.2 USW Orkney Grey

I was hoping to find an off the shelf wiring kit to add relays and also include wiring to an extra set of spots at the front. I had no luck and so have bought all the cables, relays and connectors to build up a loom myself. My plan was to use the existing wiring to the headlamps to take the trigger for the relay so that I didn't hack about the standard wiring and it could be removable.

I got lots of info from here: http://www.danielsternlighting.com/tech/relays/relays.html

Currently psyching myself up to actually start this project.

19th Nov 2012 12:09am

WelshGas

Member Since: 01 Oct 2010
Location: Vale of Glamorgan
Posts: 935

2010 Defender 90 Puma 2.4 XS CSW Santorini Black

VeeTee, according to my calculator that wiring harness is about £20 GBP.
Can anyone confirm my currency conversion.

If that is correct it is hardly worthwhile buying the bits to make a DIY harness.

BUT, does anyone know how we can buy one in UK? The site is ALL in Swedish and only seems to post internally in Sweden.

LANDYWATCH

Neighbourhood Watch for Land Rover Owners

http://www.landywatch.co.uk/smf2/index.php

19th Nov 2012 7:50am

VeeTee

Member Since: 06 Mar 2011
Location: Somewhere
Posts: 1512

WelshGas wrote:
VeeTee, according to my calculator that wiring harness is about £20 GBP.
Can anyone confirm my currency conversion.

If that is correct it is hardly worthwhile buying the bits to make a DIY harness.

BUT, does anyone know how we can buy one in UK? The site is ALL in Swedish and only seems to post internally in Sweden.

That is correct. I payed about € 20 for it (3 years ago). It is a very nic plug and play solution wich has the advantage that you can unpllug and remove it any time to have the original situation, so no wire cuts or soldering etc.

The Swedish webshop did not post anymore to abroad, so I posted a question for help on a Dutch-Sweden forum and some there was so kind to buy it for me and send to to me.

But I know a Dutch guy here who recently started a shop for this sort of mods, may be he sends to abroad?
Give it a try here Cheers, Vincent
1959 Polynorm 1/4 Ton Trailer, Olive Drab Green (sold)
1970 M416 Military Trailer (Camping Trailer Conversion), Epsom Green (sold)
1975 Series III 88 V6, Light Green (sadly sold)
1996 Defender 110 CSW 300 Tdi, Epsom Green (sold)
2000 Freelander 1 TD4 3-drs, Silver (sold)
2006 Freelander 1 TD4 5-drs Facelift Automatic, Tonga Green (sold)

MySite

19th Nov 2012 8:52am

mobilecentre

Member Since: 05 Mar 2012
Location: Evesham
Posts: 645

blackwolf wrote:
Don't forget that the headlights use different contacts in the switch to the side/panel lights. Max current on any contacts will therefore be 2x55W.

Remember also that if you have a trailer it will potentially add another 3 to 7 or so 5W tail/marker lights.

There is a single power feed in which then contacts the first position for side lights and then bridges both positions when dip is engaged.

19th Nov 2012 9:33am

mobilecentre

Member Since: 05 Mar 2012
Location: Evesham
Posts: 645

There are a few guides about relaying up headlights knocking about online on various other LR fourms.

19th Nov 2012 9:34am

blackwolf

Member Since: 03 Nov 2009
Location: South West England
Posts: 17703

2007 Defender 110 Puma 2.4 DCPU Stornoway Grey

mobilecentre wrote:
blackwolf wrote:
Don't forget that the headlights use different contacts in the switch to the side/panel lights. Max current on any contacts will therefore be 2x55W.

Remember also that if you have a trailer it will potentially add another 3 to 7 or so 5W tail/marker lights.

There is a single power feed in which then contacts the first position for side lights and then bridges both positions when dip is engaged.

Yes indeed, so there is one pair of contacts for the side/tail/etc and another pair for the headlights.

The dip switch is, in my experience, more prone to melting than the light switch.

It is a high impedance connection between the contact points which generates the heat, rather than the current flowing through the metal parts. The cleaner the contacts the less likely there is to be a problem. Arcing across the contacts (which is of course inevitable on a DC system) tends to corrode and oxidise the contacts resutling in poor connectivity and hence heat. The more the contacts are switched the worse this will, and since generally the dip switch is operated more than the on/off switch in many cases it will give up first.

19th Nov 2012 11:06am

WelshGas

Member Since: 01 Oct 2010
Location: Vale of Glamorgan
Posts: 935

Well I've registered with the site that VeeTee gave a link to. Using Google Translate I've managed quite well, but although the UK comes up on their country list, in Dutch, I cannot select a delivery method so have emailed them.

Hi mobile centre, yes I have a pdf document on how to do it, but I'm not that handy with a soldering iron and by the time I bought everything it would probably cost 2 or 3 times as much. Cannot find any suppliers of a ready made "plug & play" loom in the UK - strange. But never mind, we'll see what happens.

LANDYWATCH

Neighbourhood Watch for Land Rover Owners

http://www.landywatch.co.uk/smf2/index.php

19th Nov 2012 9:20pm

WelshGas

Member Since: 01 Oct 2010
Location: Vale of Glamorgan
Posts: 935

Just heard back from Martin regarding purchase and delivery of the Defender headlight relay loom. They can deliver to UK but there was a fault on the website so all looks good.

LANDYWATCH

Neighbourhood Watch for Land Rover Owners

http://www.landywatch.co.uk/smf2/index.php

19th Nov 2012 10:05pm

VeeTee

Member Since: 06 Mar 2011
Location: Somewhere
Posts: 1512

WelshGas wrote:
Just heard back from Martin regarding purchase and delivery of the Defender headlight relay loom. They can deliver to UK but there was a fault on the website so all looks good.

19th Nov 2012 10:08pm

WelshGas

Member Since: 01 Oct 2010
Location: Vale of Glamorgan
Posts: 935

Update.
Websit fixed and Relay Loom ordered and paid for. 50.50 Euro delivered.

Thanks VeeTee. LANDYWATCH

Neighbourhood Watch for Land Rover Owners

http://www.landywatch.co.uk/smf2/index.php

19th Nov 2012 11:01pm

Mo Murphy

Member Since: 01 Jun 2008
Location: Letchworth Garden City, Herts
Posts: 2319

1984 Defender 90 BMW M57 3.0 Diesel HT Auto Pennine Grey

What a useful website

Mo The Land Rover 90 - Many are called, few are chosen.

50 Shades of Pennine Grey

20th Nov 2012 8:36pm

kmac

Member Since: 07 Oct 2009
Location: Middlesex
Posts: 1314

2009 Defender 110 Puma 2.4 USW Santorini Black

WelshGas wrote:
Update.
Websit fixed and Relay Loom ordered and paid for. 50.50 Euro delivered.
Thanks VeeTee.

Was that the cost for the realy loom and replacement headlamp switch or just the relay loom and delivery to UK?

21st Nov 2012 5:28pm

WelshGas

Member Since: 01 Oct 2010
Location: Vale of Glamorgan
Posts: 935

Purchase and delivery of wiring loom only to South Wales. My switch is fine, at the moment. This is a preventative action.

LANDYWATCH

Neighbourhood Watch for Land Rover Owners

http://www.landywatch.co.uk/smf2/index.php

21st Nov 2012 8:40pm

kmac

Member Since: 07 Oct 2009
Location: Middlesex
Posts: 1314

Okay thanks

21st Nov 2012 9:03pm

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