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MG MGB Technical - Early B Dip Switch Confusion
Struggling through some wiring issues on the '63 B. I'm getting a new front lighting harness from Triumph Rescue because the old one is just so hacked up, I don't know where to start.
My question this time regards the dip switch. The car has a column-mounted stalk that moves forward and back (as well as the turn signals), that includes the headlight dip switch, or at least a flasher, or both(?). The wiring diagram in the Owners Manual shows that the column-mounted dip switch is optional, but shows it wired through the foot-operated dip switch. Other wiring diagrams (Haynes & Auto-Wire) show the column-mounted dip switch and the foot-operated dip switch, but they don't indicate that the column-mounted switch as being optional.
Anyway, my car has no foot-operated dip switch. Since my lights don't even work, I don't know how the column-mounted dip switch works. Does it completely replace the foot-operated dip switch?
|Greg Van Hook|
|I can't vouch for US-spec or for very early (63), nor can I get to a wiring diagram right now - however, to the best of my knowledge all MK 1 cars are the same in this area. On my MK 1 GT ('66) there is a foot operated dip switch and the flasher control is on the indicator stalk. There is a two position light switch on the dash which switches on sidelights and headlights. Pressing the foot switch turns off the dipped beam and turns on the main beam; pressing again does the reverse. Pulling the indicator towards the driver flashes the main beams. If only the dipped beams are on and you flash with the indicator stalk then both beams come on whilst the stalk is held - this is brighter than main beams by the foot switch, as in that mode only the main beams are on, not the dipped beams as well!|
Hope that makes sense!
If that is the case, can anyone suggest how I can rig up a dip switch? They don't seem to be available. Maybe just a hand operated toggle?
|Greg Van Hook|
You're looking for item 65 on this page:
It doesn't seem to be available, but the later foot operated switch (item 66) is listed as a replacement. Cost is less than £10 ($15 at the current exchange rate I guess) plus postage.
|Greg - The foot operated dip switch is the proper one for your car. The stalk operated flasher seems to be a feature that was added to replacement turn signal switches (the original turn signal switch on our 66 MGB didn't have the feature, but the replacement that I got does) Since Flashing someone to pass in Washington state is illegal, I modified the wiring for that feature and now use it to do a one sweep activation of the windshield wipers (an extremely useful feature in our climate). Cheers - Dave|
|Ok - Here is a replacement floor mounted dip switch that should work for you - http://www.vintagecarparts.co.uk/en/list+electrical~switch~dip/ Cheers - Dave|
|On the MK1 the turn signal switch flasher was only used on the GT. It was illegal in the U.S. and the dealers had to disconnect it before delivery of the car. My '67 B's switch failed in the early 80's and I was lucky to purchase the last one that the dealer had in stock. It has the flasher and only cost $30 at the time. The salesman said I was fortunate because they were NLA even back then. RAY|
|My UK spec car built in Dec 66 has a foot operated dip switch and incorporates a headlamp flasher in with the indicator switch. It's your car so you can rig it how you like, or to fit whats available.|
|I have had my 1963 car since 1968. Very early MGBs did not have a headlight flasher in this country anyway. The foot operated dipswitch is larger than the later foot operated one. |
Because I am so tall I converted to a later combination switch on the column. This gives much more room for your left foot on RHD model's anyway. The flasher is also handy as is the horn function (push the lever inwards) when you have a smaller after market steering wheel.
I had to modify the casing that goes over the later model switch to allow it to fit (Dremel) but it looks like it was made that way now and has worked successfully for many years.
|On my '64 the indicator switch failed the annual MOT test because it was worn and wasn't cancelling when the steering wheel centred.|
I replaced it with one from my (scrapped) '69 AH Sprite which unlike the original had a headlamp flasher. The '64 wiring loom had all the right connections for the headlamp flasher which made sense to me becuase I had heard or read that the headlamp flasher was always an option on an early MGB.
I am only talking about a UK car here!
I bought my 66B brand new in May 1966 in New York state, and it had the optional headlamp flasher built into the directional signal stalk.
In addition there was a change in dip switches and mounting between 1966 & 1967 models. Not sure of the break point. My 67B has the later type.
Thanks: Rich Boris
On my 69 MK11 the same as for Tim. Some time later the high beam switch was incorporated into the column stalk.
What I really wanted to say was this, FWIW.
I am seriously considering converting my floor-mounted dip switch to a footrest. This to much more comfortably prop my form whilst driving and to give my left foot a firm rest whilst underway. I will either change to a later column mounted stalk or install a manual switch to enable high beam.
|My 67 GT has the flasher and foot dip. It is not an original unit. I have two other turn indicators. One very old one without a flasher (all metal unit) and an older plastic one that has the flasher.|
|To convert my '67 to a foot rest, I installed a 1" spacer under the dip switch and used longer bolts. Works great. RAY|
In 63 it was the round type foot operated dipswitch which is remanufactured by Moss again but the bracket isnt.
The original column switch which was changed from the aluminium body to the now available plastic body never had the facility to flash the headlights and didnt have a wire in the column switch loom to do it.
The steering column cowl was also different as it just had a split up and down hole to work the indicators but later it had a slot forward to allow for the column switch flash.
In the loom you have the wires which connect into a separate loom that goes to the floor switch.
If you want to convert to the column switch dip all you do is connect the wires into the loom instead of the foot operated switch loom.
Been a while since I had a chance to play with a US flat dash car. I believe that some the problem you are having with your lighting is your lack of floor mounted dip switch. There is also a small harness that comes up from the dip switch to your main harness. Without this dip switch, or something in place of it to perform the same electrical functions, your headlights will not work. The flasher function that may or may not be on your turn signal switch is only momentary and not intended to be a replacement for your dip switch. It appears that both floor mounted switches are available through MOSS at close to $50.00 each. I am almost positive that I have a good used one that you can have a lot cheaper than that and may have a used mini harness that you will need to attach it electrically to your main harness. Without either of these items, your headlights, and may be parking lights, will not work.
|Greg Give Jim Swenson a call. You can reach him at 804-598-2511. He has a number of MG's he is parting out and he is fairly sure he has the bracket and dip switch. Probably can get the wiring also.|
|Well thanks a lot everybody for all of the good advice and help. My stalk/flasher unit is plastic and, I guess, a later replacement. It is wired for turn signals and flasher.|
I have it all hooked up. I finally figured out how the headlights were wired without the dip switch. The flasher wire (small blue/white) from the stalk was just cut and left hanging, the high beam wire (fat blue/white) was not connected to anything, and instead of the fat blue and fat blue/red wires connecting to the dip switch, they were just connected together under the dash.
I guess I shouldn't take anything for granted. Even the flasher unit was hooked up incorrectly, and the indicator light wires were crossed. So, now the turn signals work perfectly! Small victory.
The brown wire from the stalk was also just hanging. It's connected inside the stalk switch to the small blue/white wire (the high beam flasher wire), so I guess it wasn't needed as the high beams weren't hooked up anyway. The only open brown wire connector I could find was under the dash about where the radio would be if it had one. So I connected it there. IS THAT OK? Nothing has started smoking yet!
Anyway, the lights (front/rear/parking) and horn still don't work. I'm getting the headlight/horn sub-harness, and a dip switch sub-harness from British Wiring today, plus a dip switch, and thanks to Dave Dubois, I soon will have a dip switch bracket (I found the mounting holes down past the clutch pedal).
OK, on to the next topic....
|Greg Van Hook|
This thread was discussed between 31/03/2009 and 02/04/2009
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