simonpelly Posted January 10, 2018 Share Posted January 10, 2018 Hi Folks, Defender 1997 300Tdi Looking to do a wiring mod so that the current draw for the headlamps is not routed through the column switch, i.e. the classic headlight upgrade. My intention is to do this in a way that does not cut into or alter the existing wiring loom. The attached image is a proposal. Looking for some feedback. Essentially the idea is to put a pair of relays (one for low and high beams) in each of the wings. Power for the headlights coming directly from the battery through the relay (3mm cable), fused in the battery box. In this way, both sets of lamps on each side of the vehicle are still independent. Looks like it is possible to source H4 socket and bulb connectors so should be straight forward to wire up. Run the new cables in some convoluted conduit. Thoughts? Many Thanks, Simon... Quote Link to comment Share on other sites More sharing options...
Ex Member Posted January 10, 2018 Share Posted January 10, 2018 You can buy premade harnesses that are plug and play and do what you have drawn up. For the price, I can't see the point of making your own. https://www.flatdoguk.com/boomslang-performance-headlight-loom~1607 Quote Link to comment Share on other sites More sharing options...
davie Posted January 10, 2018 Share Posted January 10, 2018 second that, i have the boomslang one for about a year now and its spot on. Plug and play so no point in making own up. Quote Link to comment Share on other sites More sharing options...
simonpelly Posted January 10, 2018 Author Share Posted January 10, 2018 Great. Will take a look at that. Did some "googling" for something similar but must have missed this. Thanks, Simon... Quote Link to comment Share on other sites More sharing options...
crwoody Posted January 10, 2018 Share Posted January 10, 2018 (edited) What you've drawn is pretty much how the pre-made ones come, I contemplated the same myself about 2 yrs ago and came to the conclusion that by the time I'd bought all the individual connectors and relays etc it was a much better use of my time and cash to just buy one ready made. So another vote for the Boomslang loom. Edited January 10, 2018 by crwoody spelling error Quote Link to comment Share on other sites More sharing options...
dailysleaze Posted January 10, 2018 Share Posted January 10, 2018 I made my own as I didn't want the loom to go across the radiator as the pre-made ones do, but round the back of the engine. It's plug and play the same as your design except I fused the relays separately. Quote Link to comment Share on other sites More sharing options...
cackshifter Posted January 10, 2018 Share Posted January 10, 2018 Hi, If you have dim dip you'll need to disable that (just search on here for that). You might want to to reduce the headlight fuse sizes in the fuse box as you will be drawing next to no current through them. Most of the proprietary harnesses seem to use 2 relays and run a wire across the front whereas if I understand you correctly you intend to use 2 pairs of relays (one in each wing), to remain independent? That is a bit of a deluxe solution, but definitely more resilient. Quote Link to comment Share on other sites More sharing options...
supaimpy Posted January 10, 2018 Share Posted January 10, 2018 As was pointed out on another thread, the battery feed should be twinned so that 1 fuse going does not plunge you into darkness, the original is fused for each side. Quote Link to comment Share on other sites More sharing options...
simonpelly Posted January 10, 2018 Author Share Posted January 10, 2018 Great commentary. Intention was to run from fuse boxes and across bulk head as opposed to across front. @cackshifter - Indeed 2 pairs of relays for independence. Good thought with respect to fuses in main fuse box, will put smaller fuses in place, probably 1A. @dailysleave - Yep. May as well have separate fuses for each. Good shout. Relays probably ought to be waterproof as well I guess. My main thoughts with respect to redundancy are due to the fear of loosing all lights when driving down some dark country lane. As always, will need to "book" some time in my garage. Quote Link to comment Share on other sites More sharing options...
mmgemini Posted January 11, 2018 Share Posted January 11, 2018 (edited) Oh so modern. I was making upgrades headlight looms for cars like to those in the 1970's. all that information was originally posted om LRO.com Found where I moved the post to...... https://www.tapatalk.com/groups/landytown/headlight-wiring-a-better-way-to-get-light-t7578.html At least I suggest the correct wiring colours so anybody can follow the colours Edited January 11, 2018 by mmgemini Quote Link to comment Share on other sites More sharing options...
Mutley Posted January 11, 2018 Share Posted January 11, 2018 Cheers mmgemini...i used that thread and your info when i did mine a few years back. Works a charm and got me into having a go with electrics. Quote Link to comment Share on other sites More sharing options...
simonpelly Posted January 11, 2018 Author Share Posted January 11, 2018 @mmgemini - Thanks for your link. Liking the way you have mounted the arrangement to the wing. BTW - Was in nappies in the 70s so Defender electrics are still all modern to me With respect to colours in my diagram, should have commented that they do not reflect what is in the existing loom, just trying to get my head round it all. Quote Link to comment Share on other sites More sharing options...
mmgemini Posted January 11, 2018 Share Posted January 11, 2018 Thank you Simon. Now I wasn't getting at you over the colours, more so the people that made that loom. For those of you that "off road" the way the lights are fused, mans iff you damage a corner and the lights the fuse should save the loom. Simon, also you can take the wiring lead straight off the starter Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 11, 2018 Share Posted January 11, 2018 You can also take power straight off the alternator if you want to avoid the small voltage drop you would get going to the starter Quote Link to comment Share on other sites More sharing options...
mmgemini Posted January 11, 2018 Share Posted January 11, 2018 Yes Bowie69 but there'sa longer wiring run to keep the area clear. 6 of one 2 3's the other Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 11, 2018 Share Posted January 11, 2018 Indeed, will depend on the vehicle you do it to I guess Quote Link to comment Share on other sites More sharing options...
Stambecco Posted January 15, 2018 Share Posted January 15, 2018 On 11/01/2018 at 10:31 AM, Mutley said: Cheers mmgemini...i used that thread and your info when i did mine a few years back. Works a charm and got me into having a go with electrics. Me too! Quote Link to comment Share on other sites More sharing options...
western Posted January 15, 2018 Share Posted January 15, 2018 built my own loom, powered the 2 relays [1 for dip beam & 1 for main beam] direct via suitable fuses from the alternator, my relays are attached to the left inner wing edge just forward of the screen wash tank. my loom goes across the front of my 110. shortest cable run. Quote Link to comment Share on other sites More sharing options...
simonpelly Posted January 16, 2018 Author Share Posted January 16, 2018 Thanks Western. BTW - Loving your other thread on the engine rebuild. Hope it's still all going well for you. 1 Quote Link to comment Share on other sites More sharing options...
western Posted January 16, 2018 Share Posted January 16, 2018 Engine is going very well. Quote Link to comment Share on other sites More sharing options...
simonpelly Posted January 23, 2018 Author Share Posted January 23, 2018 Hey Folks, Cracking on well with this upgrade. Currently looking at taking power feed from the alternator. However, would be interested in views (pros/cons) as to whether earth to the bolt on the bulk head inside the engine bay or run back to the battery. Or other options? Many Thanks, Simon... Quote Link to comment Share on other sites More sharing options...
mmgemini Posted January 24, 2018 Share Posted January 24, 2018 IF ?? you read my article LOL I seem to remember that I used the original earth from each headlight connector Plus another to the front panel. Quote Link to comment Share on other sites More sharing options...
simonpelly Posted January 24, 2018 Author Share Posted January 24, 2018 Hi mmgemini, Indeed great article. Have read it multiple times. In fact, liking the metal plate bolted to wing arrangement so much that I'm heading in that direction too. Have been trying to work out your earthing arrangement as you state "Take the earth to the body/chassis." Just trying to wrestle in my mind (probably overly so) between using the body/chassis for the earth point or run separate cable to battery. Many Thanks, Simon... Quote Link to comment Share on other sites More sharing options...
mmgemini Posted January 25, 2018 Share Posted January 25, 2018 Yes Quote Link to comment Share on other sites More sharing options...
Greg110 Posted February 21, 2018 Share Posted February 21, 2018 great post, really clear and useful, Thank you mmgemini for your thread 😀 may I ask why aren’t the fuses and relays being put in the fuse and relay panel inside? As I seem to have the space inside to fit the 2 added relays, is there any reason not too? Thanks Quote Link to comment Share on other sites More sharing options...
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