Hello I recently received a free 1983 xj6 with the 7 in headlights made.by cibbi . I noticed the wires on my 72 series 1, are maybe a 22 gauge wire. All my headlight connected plugs fell apart on removal, I’m thinking of upgrading the wiring with relays for high and low, maybe possibly putting inside the buckets for protection. Anyone done an upgrade? I’m not getting very good voltage.on headlights 11v on right side and 10,5 on left side headlight. Engine running. Anyone have a schematic on how to wire relays? Possibly some main words with fuses? The stock headlight relay possibly needs to be updated or system to run these bulbs for the cibbis. Cheers
Hello Sawyer,
Try this kit from Moss, it’s color coded correctly for Lucas wiring
Or this from Victoria British
http://www.victoriabritish.com/icatalog/csc/full.aspx?Page=17
Schematics can be had on Daniel Sterns website.
Regards
cds
@sawyer10702, If you’re wondering why the links @cdscds1 are for Triumph, MG, and more importantly, not Jaguar?
That’s because the parts are interchangeable. At that time, British Leyland, aka the BL Monster owned all of the above as well as Jaguar. So lots of times If you’re looking for Jag parts, and can’t find them. It’s always worth while to look at Triumph & MG. For Example, the Side markers (lights) on a XJ are the same as the MG side markers. The head light buckets on a Jaguar (the 7" buckets are the same as buckets on a Triumph TR6).
Just in case you could care less. 
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A much simpler solution is to fit thicker wires, Sawyer…
The low voltage is caused by resistance in wires or possibly the bad connectors. Using relays would still require thick wires to the relays to feed the headlights…
Frank
xj6 85 Sov Europe (UK/NZ)
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There was a discussion not long ago…
Mark thanks for the information good to know…
Frank has in change to thicker wires, would this be from the stall dipping relay?
Thanks for the schematic! So basically my new wiring would start from the stall dipping relay? Seems pretty basic if so. Thanks for this info.
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Any long wires, too thin, will increase resistance, Sawyer - with voltage drops. The original wires were not generously dimensioned - and corroded connectors add to the ensuing voltage drop… 
Frank
xj6 85 Sov Europe (UK/NZ)
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The dipping relay will feed the new relays.
A new fat cable from the battery will then feed the new relays, you can take power from the left side positive terminal post on the firewall, very close and convenient.
Ideally, and as Frank says, you should also replace the wiring with thicker one from the new relays all the way to the lights themselves.
Aristides
… and to add to that - just to avoid it gets lost: while the original fuses are obviously sufficient to protect the control circuit, you’ll have to plan for similar fuses to protect the working circuit. David Jauch recently posted neat relays that integrate suitable fuses.
Best
Jochen
75 XJ6L 4.2 auto (UK spec)