headlights not working

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deelcee
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headlights not working

Post by deelcee »

on switching from sidelights to headlights theres a clonk coming from the glovebox area
could it be a relay thats malfunctioning? if it is where is it located?
i would be grateful for any advice
jaguar 3.8 s-type mod
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Glyn Ruck
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Re: headlights not working

Post by Glyn Ruck »

The only relay near the glovebox is one to dim the heated rear screen indicator light when you turn on head lights. The headlights are direct switched by the main switch that you turn with the levered knob.

Heated rear screen relay..JPG
Heated rear screen relay..JPG (82.93 KiB) Viewed 973 times
Heated rear screen circuit..JPG
Heated rear screen circuit..JPG (38.83 KiB) Viewed 973 times

http://www.jagstyperegister.com/images/ ... g-page.jpg
1965 Jaguar 3.8 S Type, Sync4, OD, PAS, BRG/Biscuit on chrome wires.
http://www.jagstyperegister.com/forum_n ... ?f=3&t=152
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cass3958
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Re: headlights not working

Post by cass3958 »

I will go with Glyn on this and say there are no factory fitted relays in the lighting circuit from factory. The wiring is very basic and you just had a wire from a live on the fuse box via the light switch direct to the front lights. That is not to say that a replay has not been fitted retrospectively and hidden behind the dash.
The only way to get behind the glove box is to remove the top dash wood which is held in place with four 7/16 nuts. One accessed from inside the glove box, two by lowering the facia panel down and the forth is equidistant from the side of the car as nut one but up under the dash beside the steering wheel. Once the top is removed you can remove the glove box fascia and glove box liner to look down into the void behind the glove box to see where the noise is coming from.
The picture below shows the relay that Glyn is referring to but as he has stated this is for the heated rear screen. The picture shows the void behind the glove box which can be reached once everything is removed.
DSCF6048a (2).jpg
DSCF6048a (2).jpg (663.68 KiB) Viewed 967 times
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Glyn Ruck
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Re: headlights not working

Post by Glyn Ruck »

And remember to slide the picnic tray out & remove before you attempt any of this.

Somebody might well have cobbled a relay into the lighting circuit to fit brighter higher current draw lights to the car. If the car is original you might have 2 blown sealed beams although it would seem unlikely. What happens when you turn on the lights & push the dipswitch? 4 blown filaments would be even more unlikely.

Thanks for the better pic Rob. I could not find one.
1965 Jaguar 3.8 S Type, Sync4, OD, PAS, BRG/Biscuit on chrome wires.
http://www.jagstyperegister.com/forum_n ... ?f=3&t=152
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deelcee
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Re: headlights not working

Post by deelcee »

thanks for the info!
i will check things out at the weekend
jaguar 3.8 s-type mod
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John Quilter
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Re: headlights not working

Post by John Quilter »

I seem to recall from many decades ago I had trouble with the headlamp switch. Turned out it was all gunked up with old grease (?) that prevented contact in certain positions. I was able to remove the switch take it apart carefully, clean and reassemble and it has been working fine ever since.
1965 3.8S MOD, 1990 XJ6, 1960 Morris Minors X2, 1951 MGTD, 1969 Austin America
deelcee
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Re: headlights not working

Post by deelcee »

thanks John
ill try that,
it would be nice to have an easy fix for a change
jaguar 3.8 s-type mod
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Norton
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Re: headlights not working

Post by Norton »

Hi. Just a comment on relays:
Glyn wrote « Somebody might well have cobbled a relay into the lighting circuit to fit brighter higher current draw lights to the car.»

Another reason to fit relays is to minimize voltage drop to the headlights. ( John mentioned a headlamp switch gunked up with old grease). Have done this to several old / half old cars. But then you would put an electrical wire of sufficient size the shortest way from supplier to consumer with a relay on the way. ( not behind dash ). And have had up to almost one volt improvement at the headlights. And then of course I’m convinced the headlights seems brigther!

Harald.
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Glyn Ruck
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Re: headlights not working

Post by Glyn Ruck »

Spay the whole switching unit out with CRC Switch Cleaner ~ great stuff.
1965 Jaguar 3.8 S Type, Sync4, OD, PAS, BRG/Biscuit on chrome wires.
http://www.jagstyperegister.com/forum_n ... ?f=3&t=152
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