Fail Safe Headlamps?

["tvrntgr"]

I have an S4. Dash was removed to refinish, when reinstalled the
headlamps are on with key, switch does nothing. I have identified
headlamp relays and a third relay,other than the horn relay. The
repair manual doesn't give info. What do I look for to to get ligts
off and dimmer to work?

Thanks for any insight, Jerry

[BenL]

Some Elans have a weird feature. If you raise the headlights without
turning them on, they'll automatically flash the high beams. This
feature is not in the US version of the cars, but you can find it in
the wiring diagram. I don't know if your car has this feature, but it
might explain the extra relay.
---Ben

["tvrntgr"]

M car is not USA version, RHD, was brought in about 1980, key was put
on stering column, brake warning light added, emergency flashers
installed. I found some goofy wiring, repaired and returned key to dash

Jerry

["gcurtin"]

My early US Modified S 1 has the flasher installed and the dim switch on
floor. on the way back from factory on the A1 at night I lost the
headlights. Had to stop at three gas stations before I found a hair pin and
Band-Aid to by pass the relay and give me high beam head lights. The only
problem was they were set for the us there fore into the eyes of the cars
coming the other way. Not a problem on the A 1 but one on local Yorkshire
roads. When I returned to the factory the next week they had to go to the
engineers table to find the drawings to trace the problem. That was Lotus in
63.

Gerry Curtin

[richboyd]

The real solution to wiring issues is to understand how each
sub-system should work, or how you would like it to work, and then
create a wiring solution that does the job. Trying to figure out what
the factory intended, and how they attempted to lash up a wiring
harness, and then trying to exactly re-create the factory's fuzzy
electric logic, is folly. That is my opinion.

Stated another way: we are dealing with old cars. Most of our cars
have been "fixed" by previous owner. The factory's wiring was
Byzantine to begin with. How could Lotus so complicate such a simple
wiring system? Lucas components didn't help.

We need to take responsibility for understanding the functions of our
car's electric systems. No way around it. I don't think that we
should repair our cars by reverting the original wiring system. Too
much time under that bridge. Toss out the micro-switches, vacuum
whatevers, Mickey-Mouse patches made over the last 35 or 40 years
... Get to understand some simple electrical fundamentals and create
wiring subsystems that work well, make sense, and don't re-create the
original mess. Better yet, re-wire your car from scratch while doing
your restoration job.

That's my two cents worth.

Rich Boyd

[Gordon Sauer]

Sounds good but the problem is--how well it's done. My cars PO did a really
nice job of putting in wiring to better handle loads, using relays, putting in
electronic ignition--all in red! I bought an original wiring harness that
I'll put back in. Gordon Sauer

[lotuselan2]

Rich

Amen to what you say.


My PO did me a favor and cut the harness in two half way down the side of the car. That told me to just wire it from scratch myself. I did just what you said; I took it function by function and wired it. A little trial and
error in a few places but it went easily. I wrapped wires with heli-wrap
not tape which makes it easy to make additions or changes. I made my own wiring diagram and I believe I have about 60% as many wires as "original".

Ken

'69 Lotus Elan +2 with BDR

[poiuyt]

I have an S4 with the lights that are raised by vacuum - don't know if
that's what you have, but the problem may be the installation of the
dash.

If the lights worked ok before the dash was removed you may have a
short between the switch contact on the back of the dash and the
bracket that connects to the tunnel to the top of the dash cover. I
had problems with this when I installed the dash and had to put a sheet
of rubber cut from a bicycle inner tube between the switches and the
metal bracket.

It's a possibility if the power contact is shorted to ground (the
bracket), operating the switch relay and keeping the lights on every
time the ignition is turned on.

[kayenney]

Ken,

Could you let me have a copy of your wiring diagram please?
Are you running an alternator? Negative ground?

Ken Evans in NW Florida
'69 Plus 2 TC

["tvrntgr"]

So we have a group of 900 members, no one knows how the light circiut
works and the best info is to reinvent the wheel

Jerry

[poiuyt]

Well, between the car being a Lotus, with no guarantee any two cars
were wired the same and whatever the POs have done, there may be 900
different ways the lights have been wired!

Steve B

[Bill]

Well I am not about to pull my S1 electrics apart to prove to others that there is a flashing position on my headlamps - the other relay?- but there it is. I still use it to warn the old farts (older than me that is) that they are about to be speedily overtaken. A touch of the tooters as well of course.

Check out the recent listing of the early shop manual, better yet, load your printer with a ream of paper, print it out!! - then you will have the basic (early) wiring diagram.

Keep your stick on the ice boys!

Bill (26/0538)

[Elan45]

Having to insulate the switches from the dash sure scares me! Can you
say FIRE HAZARD. Steve, you've got something seriously wrong.

Jerry,

When I bought my S3-SS in 1974, the light switch had failed, and since
this was a Super Safety that uses the same rocer switches as a S4, that
was what was needed. But, the DPO (yeah, we had 'em back then too) had
ordered a switch based on the VIN of the car and the parts book says SS
models started at 45-7400, but we now know that they started quite a few
numbers before that. So, he'd gotten a toggle switch from Lotus East
Distributors and had to re-order to get the right one. So, the wires had
been jerked off the dash mounted switch and fitted to a switch hanging
loose from the edge of the dash. I guess where I'm going w/ this is;
perhaps the headlamp switch may be defective and an easy way for your
DPO to get power to the lights might have been to pick up power right
from the ignition switch, which would cause them to be on any time the
ignition was on.

I have found over many years of Elan ownership, that the wiring
schematic for the S1&2 is basic to all Elans. When I've had to do major
work on both my early FHC and the S3-SS DHC, I've found the S1-2 diagram
the one to use. Especially the early FHC, the wiring matches the S1-2
diagram precisely except that there is a jumper to the window circuit
and an additional terminal on the interior lamp switch to power the
lamps mounted in the rear pillers.

My advice is to look at the S1-2 diagram in the manual until you
understand exactly what the circuits are doing. Then go back under your
dash and sort it out. Now, that's not to say Lotus did it the best it
could be done. The relays in the Elan are all used to make the headlamp
flasher system work, and do nothing to keep the full current of the
headlamps from going through the switch. I've wanted for years to sit
down and redesign the circuit to make the headlamp switch and main beam
switch carry only trigger loads and the full current to go through
relays, but since it has continued to work just fine, I've let the
sleeping dogs lie.

Roger

[Rob_LaMoreaux]

No it just means that we're either too busy, or can't find the information
at this time.

Somewhere I have a file with the marked up S4 wiring diagram I made to
include the failsafe headlights, but I can't find it at the moment and the
marked up wiring diagram is somewhere at home.

The way the failsafe switch works is quite simple. When the switch is pulled
out one microswitch closes to turn on the relay to the headlights supplying
power to either the high beam or low beam relay depending on the switch on
the steering column. The other microswitch turns on the parking/running
lights.

I keep meaning to mark up the color Autocad drawing done of the wiring
diagram, but I haven't.

If the lights are always on, no matter whether the switch is in or out it
could be a few things. It could be that the wires are on the wrong leads of
the microswitch and the switch is adjusted wrong so the never opens. It
could be the steering column switch is hooked up wrong, or the relay is
wrong.

It is really hard to diagnose this over the email, but I'll try to help
anyways.

First turn on the car so the lights are on with low beams selected. Now
disconnect the power going into the low beam relay coil. Do the lights go
off? If so the output of the relay is connected correctly for the low beams.
If not disconnect the power to the coil of the high beams. If the lights go
off then the high beam and low beam are backwards, but the relay side is
correct.

Aarghh. I'll have to find the diagram, since I can't think how to give you
steps without confusing the h3!! Out of both of us without it.

Rob LaMoreaux

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