The largest and best supported Jaguar cars enthusiast site on the Internet!

Serving Enthusiasts since 1993
The Jag-lovers Web

Currently with 3,166 members

XK120 Light switches

XK120 Light Switches

I wonder if any owners of very late XK120s might be able to tell me whether
they have a 3 position (usual) or 4 position (maybe) main light switch
fitted. Usually for a 4 position the plate would have said "F" for fog
lights, but I am not aware that any 120s ever had this. Still, there may
have been 4 position switches fitted without using the 4th position. You
would have to operate the switch to see. Cars that would be in this late
category are owned by (surnames only) Hodson, Kanter, Baysinger, Rosenberg,
Wahl (ex), Brady, so if any of you can help ... - Regards, John Elmgreen

John, George, Brian Pel, Roger, or anyone else who can help,  I have
managed to get the front crash roll and dash boad upholstered and set in
place, allowing me to continue with the wiring. John your question on light
switch type came at exactly the right time for me. On my early 140 roadster
I have a switch with 4 positions, Off and 3 other positions. I would
imagine that the first position from off should bring on the sidelights,
and dash lights, The 2nd position should leave everything in position 1 on
and bring on the headlights. The 3rd position would add the fog lamps
leaving everything else on. Can someone confirm my assumptions are right.
The problem is that if the above is correct, the switch installed in my car
does not produce the correct connections to achieve this. The switch will
alow me first bring on the sidelights/dashlights, in the next position the
headlights will come on, leaving sidelights on. In third position
headlights would have to go off and fog lights would come on, leaving side
lights on. An alternative wiring diagram I have seen shows that a seperate
switch is energised when main light switch is put into position 1
(sidelight position). This arrangement would allow you to have all lights
on at the same time. I do not believe my car had this arrangement because
although there were a number of additional switches installed I think they
were added by a previous owner. The wiring to them was not original and
they are not Lucas. The switch itself only has a "0" showing the off
position. The other 3 positions do not have any markings as to what they do
for you. Hope someone can straighten me out as to what I should be trying
to achieve. - Thanks, Neville Laing

The way your four position switch is wired ie. when the fogs go on the
headlights go off and the sidelights stay on is the same as my Mk 2 with
factory foglights. This may be/was a legal requirement in the UK as it is
here in NZ. ie. fogs and headlights should not be both on at once. - John

John, I looked in my Jag books, Lucas books, et all and can find no
reference of a 4 position switch for the XK-120. The fog light switch was a
single switch, Jag P/N C2744, Lucas P/N 03126 and there was no reference to
mounting position. The books did show different cable lengths dependent on
1 or 2 lamps fitted and Rh vs Lh drive. - George Badger

Neville, With the four position switch: position 0 is off -O; position 1 is
sidelights only -S; position 2 is sidelights and headlights -H; position 3
is sidelights and fog lights -F. Every XK140 that I have seen with the 4
position switch has been wired this way. These include Concours cars. I
also have an orginial bezel from a XK140 with these markings. I'm thinking
that the other configuration with an separate fog lamp switch might have
been a dealer installed option. Can anyone in the group say for sure? -
Cleo Bay, XK120, XK140

Hi Neville Laing & all -- on my original Mk IX, 792817 BW, Date of
Manufacture 15 Dec. '59, headlamp switch is four-position -- on bezel: O
(off); S (sidelamps including license lamps); H (headlamps plus all above);
F (foglamps but no headlamps, all others above). I hope this is helpful -
Larry Martz

Neville, The light switch in your 140 is correct. It is only an american
convention (law) that requires that the H/lamps be on when any aux lamp is
on. O = all off, S = only side lamps, H = head lamps and F = fog lamps. The
side lamps remain on in all positions except O. - George Badger

Ditto my Mk II sold here in the US; when the fogs come on the headlights go
off. - Dick Rowley

I second John McDonagh's opinion. My USA spec. Mark V is wired this way,
either foglamps or headlamps, but not both together. I don't know if it was
a US requirement or not. It has a 3 position switch with a handle that
looks like a boat rudder, and the fogs are wired thru the sidelamp position
and controlled by a separate switch. Took me the longest time to
accidentally discover how to turn them on. My 120 is early so it has the 3
position switch with the T handle. - Rob Reilly

A few XK120s were fitted with fog lights. Is there anyone on the list who
has these, apparently from original? According to the parts book, they came
with a separate Lucas switch and were therefore no operated from the normal
switch. However, I do want to double check this. Could you tell me if yours
are operated from your normal light switch, or from a separate switch? Does
your normal light switch have an "F" setting (like the 140s and 150s did,
where fitted with fog lights)? Or does it have a 4th switch position but
without any F indicated on the switch plate? I ask this because one of the
late 120 light switches is listed as a 4 position switch (which implies its
use for fog or driving lights). Or if a separate switch for the fog lights,
where was it fitted and what did it look like?
By the way, thanks for recent messages with car numbers and other details I
have been chasing up over recent weeks.  - Thanks as always, John Elmgreen

John: Perhaps my '54 qualifies as well. 3 position switch in this one.  A
fellow at Carlisle this past spring (from a firm called "British Miles")
had a 4 position switch he was selling for a tidy sum, representing it as
being quite rare and having come from an XK120. The bezel did indeed
feature an "F" in the fourth position. Bearing in mind that SE models came
standard equipped with fog lamps, one would think that these might have
been the first to acquire the four position switch. - Nick Saltarelli, 1954
XK120SE OTS, 1968 E-type OTS

My 140 FHC has the 4-position switch as well, but no fog lamps or evidence
of them (and no lettering remaining on the bezel). Does this mean the car
had them at one time, or that the 3-position switch parts bin was empty
that day? - Regards, Jim Voorhies

The Fog lamps work separately from the head lights. The operation of the
switch you describe is correct. - Lee Eggers

Several people have referred to regulations restricting fog lights and
headlamps from being on at the same time. Well, that law must have changed
in the US because my new Ford pickup has foglights that go on only when the
headlights are on (but the headlights must be in the dimmed position). By
the way, it is ok to mention a Ford on these cyberwaves, isn't it? After
all, who owns Jaguar? - Carl Hanson, 1951 xk120 fhc, 1997 Ford F150

Ditto for my (former) 1982 and 1983 Toyota Supras (in Canada). I rewired
the fog light switches in these cars to the ignition switch-controlled
cigarette lighter feed so that I could have more control over the operation
of the fog lights, ie. using them without having the headlights on.  - Dave

The law in California is that aux lamps can not be used without head
lamps(dipped beam) being on.
I believe the laws in the various european markets stated that when the aux
lamps operate,the side and rear lamps must be on. Hence the turning off of
the headlamp circuit when the aux lamps are turned on, the side and rear
lamps remaining on throughout the operation. Many of the new cars fitted
with factory aux lamps require that the head lamps be on in dipped mode
before the aux lamps can be turned on. If installed by the dealer or owner,
anything goes and often does. - George Badger

If you have any questions or comments send e-mail to:
Main Page Back to the Library


Please help support the move to the new site, and DONATE what you can.
A big Thank You to those who have donated already!



Go to our Homepage
Improve your Jag-lovers experience with the Mozilla FireFox Browser!

  View the latest posts from our Forums via an RSS Feed!

Jag-loversTM Ltd / JagWEBTM 1993 - 2023
All rights reserved. Jag-lovers is supported by JagWEBTM
For Terms of Use and General Rules see our Disclaimer
Use of the Jag-lovers logo or trademark name on sites other than Jag-lovers itself in a manner implying endorsement of commercial activities whatsoever is prohibited. Sections of this Web Site may publish members and visitors comments, opinion and photographs/images - Jag-lovers Ltd does not assume or have any responsibility or any liability for members comments or opinions, nor does it claim ownership or copyright of any material that belongs to the original poster including images. The word 'Jaguar' and the leaping cat device, whether used separately or in combination, are registered trademarks and are the property of Jaguar Cars, England. Some images may also be Jaguar Cars. Mirroring or downloading of this site or the publication of material or any extracts therefrom in original or altered form from these pages onto other sites (including reproduction by any other Jaguar enthusiast sites) without express permission violates Jag-lovers Ltd copyright and is prohibited
Go to our Homepage
Your Browser is: CCBot/2.0 (, IP Address logged as on 24th Sep 2023 04:57:44