Grounds connection for front headlight assy

(Jochen Glöckner) #21

Thanks Paul, again,

indeed, it is much like being more confused, but on a higher level …

Now I know the type of earth connector to learn they are wrong anyhow - at least most likely they are.

Yes, I’d appreciate if we collect some data points to find out what these connectors looked like originally, no matter whether SIII, II or I. So, yes, I’d be more than happy if you could take some pics of your cars. Maybe others can check out on their SII cars.

For the moment the only thing I’m pretty sure from the SII wiring diagram is that all grounds for outer and inner headlights as well as fog lights have an earth connection via cable.I just can’t get over Jaguar omitting every bit of information on the hardware side of the harness mountings in the official documents. It feels a bit like the criminal investigator digging into old files and finding that every bit relating to a particular person is missing …

Thanks again


75 XJ6L 4.2 auto (UK spec)

(David Jauch) #22

I still think they are these.
I‘d use them without worrying about the water. If I was, option a. Is to use a longer wire and b. To connect it otherwise - my S3 has a bodged spade connection and the chassis connector is via Dougs description. Sorry, by the way, Doug, you even wrote paint - was I thinking?
I wonder if gold plating the connectors would help.

(Paul M. Novak) #23

Here are four pictures of the inner headlamp grounds in my Antelope 1984 XJ6 Vanden Plas (left), my Jaguar Racing Green 1990 V12 Vanden Plas (left and right), and my 1987 XJ6 parts car (right). These are all Series III cars and the grounds are pretty much as Doug described. I hope these pictures help. I know that your car is a Series II so it could have been different than what these pictures show.


(Frank Andersen) #24

That was an inlet backfire, Carl…

Generally thought to be caused by lean mixture - like you may have (had) an air leak? Or some other cause…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

(Doug Dwyer) #25

There’s nothin’ like adding a bit of bling to your grounds, David :smile:

Fixes can be as elaborate as the imagination and pocketbook allows. That’s part of the fun! For those best described as boring and impecunious, however, the method I mentioned is perfectly adequate. I’m finding myself in this category increasingly often. :slight_smile:

With respect to the headlight grounds in particular I’ve oft thought that lengthening the wires to create a new ground point in a less weather-exposed location might be a good idea.


(Doug Dwyer) #26

I hear ya, Carl !

Yep, Vaseline will do the trick…as long as it’s used in a cool area. I think it liquefies rather easily.

Over the years I’ve used silicone paste, dielectric grease, wheel bearing grease. Boat trailer wheel bearing grease is especially good…water proof and very sticky. Use any of 'em on newly-cleaned grounds, bulb sockets, and slide-on connectors and you’ll be ‘good to go’ for a long time.

Many manufacturers pack lamp sockets with some sort of grease, usually white. I’ve never known what is was, specifically.

There are lots of specialty products out there. I’m not against using them, mind you, but over the years I’ve found that generic whatever-you-have-on-the-shelf substitutes work perfectly well.


(Carl Hutchins, Jr. ) #27

Frank :

Definitely in the inlet! that is why it blew off the air filter!!

Son opines, a slack timing chain. The real mileage of the engine is not known. And the episode caused a sensor, probably the knock sensor to relate to the PCM. PCM recovered with time. And,. the car runs fine…


(Jochen Glöckner) #28

Thank you all!

Clarification is good. Obviously there have only been single ring connectors for the inner headlight grounds at least on SIII cars - no bullet earth connectors, nor sleeve earth connectors, as per your pics, Paul.

Doug is of course right - it would be the cleanest and safest solution to insulate all electric devices and carry the path back to the battery with a separate wire. - Until some decades ago it was common on bicycles to only have a wire for the positive path and use the bicycle frame for the way back. I cannot remember how many times I desperately tried to restore the function of the light on such bikes. For the last twenty years or so it has become common that bicycle light systems come with hub dynamos and two wires and it didn’t even take LED lights to make them reliable and resisting even the crude elements bicycles are exposed to. - An easier version for cars would be to take the ground wires through a rubber grommet into the cabin and provide for grounds in a clean and dry place.underneath the dashboard maybe.

Thanks again


75 XJ6L 4.2 auto (UK spec)

(Mark Lee (Pay Pal Patron)) #29

These are also available at just about any elect-chicken supply house or just about any big box store homeless deathspot aka Home Depot (in the US). I’ve got boxes of them.

(Jochen Glöckner) #30

Thanks Mark,

I’ll try to find some fitting wire ends around here. I should find something.With the better weather under way I’ll tackle the fog light job again in April I guess. Till then I’m pretty much booked out.



75 XJ6L 4.2 auto (UK spec)

(Carl Hutchins, Jr. ) #31


Headlights offered the first learning lesson on my SIII.

Not long after it came here, the right outboard lamp went dark! No big deal. I’ve been there done that. Easy, install a new “seal beam”. did that. A tad trickier than on my prior USA critters. But,. I managed. @@@#$%$#. Still dark!!!

Fussed around and found the black wire with the eyelet. That is ground in any language/

Removed it. cleaned it. Screwed in the fastener. It lit. Good, it is brighter than the others. Oh well…

Decades later, swapped out the other three. All now bright. Conversion to 7" project stalled on the bench… It looks like that is where it will end.

Battery was low the other day. Not enough to crank. A few hours on the Smart charger. all well. Lots of volts. Happy crank and fire. May drive it to market today…

chopped on my “Sconce” project. got some more shavings out. Might go to plan B and make an agressive chop. And have material for two smaller ones!!! Way back, was instructed to make any moves, bold ones…


(Jochen Glöckner) #32


as for your headlight conversion project I guess your decision is based on the balance of eyes and bones: if you can’t see at night, you’re highly motivated to put in 7" H4 light and even more so, if your bones don’t object to fool around under those eyebrows. OTOH, if your eyes are good, but the bones hurt, you’ll probably let that project on your bench forever.

BTW, having changed the headlights twice - the first time because the ones in the car were rusty, the second time because I failed to plug the hole for the pilot light and the new ones rusted out again - I can say that this is really the kind of project you can invite your son for an easy Saturday afternoon. With a small bench to sit on in front of the car at the correct working height it is a piece of cake with the correct parts.

Good luck


75 XJ6L 4.2 auto (UK spec)

(tony) #33

Hi gents,

Are the XJ fitted with headlight relays, if not has anyone fitted them?

(Frank Andersen) #34

Not fitted ex factory, Tony - but some have…

Main reason is to reduce wire resistance for more light - but doubling wires is as efficient…:slight_smile:

xj6 65 Sov Europe (UK/NZ)

(tony) #35

my main reason is to protect especially my light switch, but also in-cabin wiring

the secondary reason is brighter lights

(Aristides Balanos) #36

Yes, I did, and I highly recommend it.
The difference in light output is substantial and no more sparks coming from the stalk switch.
Of course it was combined with bigger gauge cables feeding lights.


Cibbie headlights conversion
(David Jauch) #37

I did last month. Four relays, where the fuse box was. The power feed wire was simply the thickest I could find. I modified the fuse box bracket to take the relays instead and tossed the fuse box in favor of fused relays. (The Real improvement is whenever you can get rid of a glass fuse!)
The switch and relay feeds now power the relay coils, the ground connection is right there anyways. The power wire was fed through the channel in the fender, with protective tubing of course.

One relay each (for safety) is used for the low beams, and one each for inner/outer highs. So far it works beautifully. I didn’t bother to change the wiring forward, still a bit brighter and much more reliable. also, the hella relay should now outlast me. Adding a resistor to it’s coil might drop the current for the hella, but I think it will keep working fine.

Took me three or four hours, with the relays already put together so I only had to make sense of the wiring and cut/splice them in. I wish it would look a bit more original, but the four relays are needed and so I can’t hide them there. One could mount them at the lamps on the hood, with extra power wires!

(Aristides Balanos) #38

A resistor will greatly help the stalk switch life expectancy.
Instead of a resistor though I added an extra relay between the stalk switch and headlight relay.
Slightly over-engineered but it absolutely did the trick.


(David Jauch) #39

What about the 1.8 ohm in between? I’ve seen the relay, but now I also see a resistor in your schematic.

I didn’t fuse my relays - did you think it was necessary?

(Aristides Balanos) #40

I first added the resistor, before I add the relay, the headlight relay was working fine but the stalk switch was still making spark noises, added the extra relay and left the resistor in place.

I think it is, otherwise the circuit from the battery to the headlamp switch and then to the relays is completely unprotected.
I used in-line fuses.