Main beam electrickery question

[dazzer]

Ok you electrickery experts.

Is it possible to retain the main beam foot switch AKA 2000 mk1 but to add a dash switch so that either/or could be used for the main beam. If so how would the wiring be configured?

Dazzer

[sparky_spit]

It would be difficult using normal high/low beam switches as they just have single pole changeover operation. If you wired them in parallel then you could get in the situation where both beams are on or you are on low beam but the dash switch is in the high position.

What you are looking for is the operation that upstairs/downstairs house wiring uses at the top and bottom of staircases; either switch turns the light in the opposite mode to how it was beforehand. I can't think of a way to do that with just the standard switches.  You will also need a couple of relays too so that you have a synchronised changeover function from both switches.

Unless someone can think of a relayless solution?

Not knowing the big saloons that well I assume the foot switch just toggles between high and low without you knowing which is which if you don't watch the lights?  And the dash switch has a proper main beam position and a proper low beam position?

[Nick Jones]

I think you need relays.  Would be much simpler if the dip switches were just momentary too - then it could be arranged so that tap from either would just change the state.  It's probably possible with the original switches plus relays but it's making my head hurt......

Nick

[dazzer]

Hi Sparky Spit

The light switch is just side lights and dipped seperate on tje dash.

There is a dip flash on the indicator stalk and the main beam on/off via a foot switch.

Yes you have to check the main beam blue warning light to check if the main beam is on.

Problem with the foot switch is that if operating the clutch or braking (its on the clutch side of the footwell)
Then the main beam has to stay on until the left foot is free

[dazzer]

I suppose just extending the wires and fitting a dash switch would be more straight forward.
Looks pretty heavy duty though ... 25 amp +++. Any ideas?

[TedTaylor]

Pretty sure I have mentioned this somewhere before, but I dispensed with the foot dip switch on AFH when building it as a period (i.e.early 1960s) rally car and fitted a period flick switch with a metal 2 inch exctension stalk

Important you use a suitably strong switch as they can have an annoying habit of breaking.  Don't use plastic but one where the metal stack goes into the switch internals.

MUT

[dazzer]

That looks perfect Ted.

Ive also got switches either side of the centre console grill.

Great period set up.

Darren

[TedTaylor]

The switches on the raised 'box' with the instruments on was done that way for the dip switch because it sits close to the widest part of the steering wheel and is close at hand to operate quickly with a finger

MUT

[sparky_spit]

To make a proper job you need a 3 wire switch system between latching relays. That will allow each switch to always be in the right position for high and low beam. The relays are not just there to cope with the current draw, but to unlatch when the other switch is operated, keeping the orientation of the switches correct for the beam that's just been switched.

I need a fag packet and blunt pencil to work out the diagram.  It won't be pretty but will work. If too tricky to wire up, just parallel up the two switches and accept that you might have both lights on at once if you forget which switch you used last.

[Davemate]

Quoted from dazzer

I suppose just extending the wires and fitting a dash switch would be more straight forward.
Looks pretty heavy duty though ... 25 amp +++. Any ideas?

You only need to extend one wire over to a dash switch

Unplug one of the wires from the foot switch and extend it to a dash switch then return a new wire back from the dash switch back to the foot switch

Result :-
Both switches have to be on for the main beam to work but once on if your foot is to busy then flick the dash switch and the main beam goes off

Other options:-
1)Use the overdrive lever for main beam and add an overdrive switch to the gear knob so doing away with the foot switch
2) just do away with foot switch and just have a dash switch
3) leave it as it is and just live with it
4)extend foot switch wires and an coiled wire to a switch on the steering wheel

[thescrapman]

The foot switch is a 3way switch, so you could use 2 of them and then a relay to switch between dip and main.

Will try to get my head round a wiring diagram.

[dazzer]

Hi All

Thank you for taking a look at this. I got quite excited at Davemates suggestion. Unfortunately it doesnt work on my loom in practice anyway i placed a switch between each
of the three wires in turn which produced. 1) No change. 2) front dipped and mains out. 3 front dipped and mains out... i know the lighting circuit is all relayed. Perhaps that makes a diffetence? Its a new loom and 4 x relays from Autosparks...

[Davemate]

To be honest I didn’t think about my answers to hard
It also slipped my mind that there are three wires on the foot switch
1) must be a constant feed or earth,mk1’s are wired weird
2) off to dip beam circuit
3) off to main beam circuit

Sorry to have raised your hopes  
Can’t think of anything other than my “other suggestions” which all involve removing the foot switch

[thescrapman]

Worked it out.

See attached picture

[dazzer]

Wow Colin are you sure thats not a diagram of a Flux Capacitor!

Cheers Darren

[sparky_spit]

That diagram is similar to the upstairs/downstairs domestic lighting one.  It works but the switches will be in different positions (up or down) for main and dip depending upon which was last used. That's fine for the floor switch but confusing for the dash mounted one?
If that's okay then fine. If not you'd need a relay for main and another for dip, latching on each others operation, delatching on each others release.

[dazzer]

Thanks Mike

Cheers
Darren

[dazzer]

OK after much phaffing decided to do away with the foot switch and affix a straightforward toggle switch near the steering wheel.

For reference and quite conveniently the wires easily re route from the floor up through the column with a little spare for whatever arrangement you prefer. I didn't have the correct switch available this weekend (to enable the dip to be off as the mains come on) however I had a nice 25A long toggle which works but brings up the mains with the dips still on. I'll swap the new switch in this week. Whilst playing with switch positions came up with utilitarian yet really nice switch positions for the main beam and momentary overdrive switch. Not for the purist but position is perfect. Looks a bit mad max meets scrap heap challenge. To achieve this you need to rake through that tin of surplus useless bits you've kept over the years and locate a couple of brackets (mine are from an old seat belt fitting kit) Bolt them together and there you have it.

[efp]

Love it. You must have been a wiz with Meccano in your youth

[piman]

Hello Darren,

for that period look slip a piece of suitabl bore rubber or plastic tubing over the switch toggle, trim to length to extend it closer to hand.

Alec

[dazzer]

Thanks Alec

I like period touches like that.

As a further update I tested the lights last night and luckily living in the sticks 'Up North' was pretty much on my own so plenty of time to fiddle. Whatever is written about lighting there is no comparison to actually getting out and about on country roads with ups, downs corners etc.

So the verdict is that with dipped and mains on together there is noticeably more coverage than just mains or dipped which is reassuring when going over the brow of a hill, the dipped illuminates down a little over the dip and also gives general peripheral lighting.

I'm using Cibie upgrades on the dipped/main (outers) and all lighting is separately relayed so no problems with current/draw.

You can get the same effect on a MK1 (or on mine anyway before the switch and new loom mod) if you pop your mains on and then use the flash, as it lights up dipped as well.

Rally escorts used to mod the lighting to bring up dipped and mains together in the day and many moderns keep the dipped and mains on together. My 08 Vectra being one that does.

Cheers
Dazzer