Went out in the dark which I rarely do and didn't realise just how bad the headlamps were I believe you can buy a harness with two relays in that plugs into headlamps anybody used one and had any success. Cheers
Welcome. It would be helpful for those helping you if you put some base information about your car in your signature, Year, AC or no AC, major modifications etc. There were basically three primary wiring systems in the X over the years (thus why the links Steve offered show very different solutions) so knowing what you have helps us direct you to or provide advice and info which will help you most. Help us help you
Most of the kits you see use substandard guages of wiring, if you are at all handy with wire crimping or want to become good at crimping, this is a great opportunity.
Bob Brown, one of our forum members, made very nice sets which replaced much of the existing wiring and added four relays (two per side, high and low beams) with new sockets. Once in a while you will see them for sale.
The reasons for poor light output start with the connection in the fuse box that brings power to the brown wire which feeds power to the ignition switch. This junction can become overheated and the connectors become loose. The next area is at the other end of that brown wire at the connection to the ignition switch harness which can also become overheated, after that the connections in the switch itself where high loads can degrade the metal contacts due to heat. Further down the chain is the light switch itself which is an X specific part which also can suffer from carboning up and overheating. After that, the connections in the fuse box can be problematic as the fuses may no longer fit well and followed by the connections to the bulbs themselves and finally the ground connection back to the body can be compromised by corrosion.
To start resolving the problem check the simple things first, which on any old car are the grounding connections. Upgrading the main ground wire from the battery to the body is an easy step as is making sure the bolted connection at the body. Follow that up with the ground connection of the wire to the ground bloom and unbolting the bloom from the body to clean that connection (doing this step around the car can improve function across the car if you clean up the various ground blooms and ground wire connectors).
Folow that with verifying the quality of the supply connections I mention above. There are many web sites where you can find info about cleaning electrical connectors and the materials to use, lots of opinions around this so I will duck that discourse. Each connection is a potential voltage loss so ensuring the wiring connectors are clean and tight will improve things.
The ignition switch is hard to take apart to clean the contacts within, they can be taken apart by drilling out the rivets and then reassembling using long screws with nuts. There is a MiraFiori.com how to around taking apart the 124 ignition switch, the X switch is very similar. Midwest-Bayless.com does offer a new Italian made ignition switch if that is faulty and can’t be serviced (you loose the connection to the key warning chime).
https://www.mirafiori.com/faq/content/switch/switch.html
https://www.mirafiori.com/faq/content/switch/index.html
There is some discussion about how to improve things with relays in those links instead of the ‘brown wire fix’ which puts more power into the ignition switch which can accelerate the degradation of the ignition switch.
The headlight switch is another area where heat and carbon buildup can reduce the power transfer to the lights themselves can happen. This switch is now rare (some versions of it extremely rare) but can be taken apart to be cleaned. Some internal parts of the switch are common to other switches which were used in Xs. Here a few links to this procedure, I think there are a few more around here as well:
https://xwebforums.com/forum/index.php?threads/switch-internals.44634/post-432276
My headlights haven't been 100% reliable switching-on and I suspect my switch is a little flaky so I disassembled it. Some of the contacts were a little cruddy and the spring loaded arms that slide across the contact arms are worn -- especially one of them. I'm planning to clean all the...
xwebforums.com
The fuse connections can also be cleaned up like any other wiring connection and the tangs re-bent to provide better contact to the fuse depending on the version of your fuse box. There are also new fuse box assemblies where you can replace the existing ‘torpedo’ fuse approach with the modern blade type boxes. A Ukrainian company, LadaPower.com offers good servicable units which can be wired up to replace the now quite old fuse assemblies in the car and get rid of the those half length torpedo fuses you may have.
Lada Niva / 2101-2107 Fuse Box + Fuses EURO (13 fuses) Electric 1600
www.ladapower.com
The how to is here:
Bought this 13 ATC fuse block from Ladapower: http://www.ladapower.com/index.php?option=com_virtuemart&view=productdetails&virtuemart_product_id=2501&virtuemart_category_id=46...
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Then there is adding a kit as you first asked about:
I have been working my way through upgrading the lighting on my 85X. This past week I installed LEDs in the tail lights, front and rear turn signals and reverse lights. I put the proper LED flasher in the relay tray. Somehow, I forgot to order the marker LEDs and license plate LEDs. I will get...
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And finally jumping over many of the electrical issues, one can go to the Jeep 7” LED headlights which some have chosen to reduce the power load and increase output all in one simple replacement. That they are bizarre looking on an old car is less of an issue with the X due to them being stowed most of the time.
I hope some of that helps.