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MG MGB Technical - Fog and driving lamp switch

Where on the 66 MGB dash is the fog lamp switch placed? How about the driving lamp switch? Does anyone have a car factory fitted with both?

The wiring diagrams shows each type of lamp is wired differently, so it is possible that a car may have been made with both which means there would be two switches, one for the fog and one for the driving lamp.

I tried a search in the archives for "fog lamp switch" and it returned nothing on the switch location.

Blake
Bullwinkle

Driving lamps and fog lamps are two different types of lamps and should be used in different weather conditions. There would not be a need to have three or four lamps on your car. Note; under U.K. law you need two driving lamps where as you can get away with only one front fog lamp (at least on older cars), I would assume it is the same in the States.
On a 66 I seem to recall that there were no blanked off switch locations. If that is the case then the switch and a warning light would be placed anywhere so that it was within reach of the driver. But I may stand to be corrected on this latter point.
Cecil Kimber

Just ditch the B and get on A--the driving or fog lamp switch was factory installed, although the lights were an option. Mine has a switch to nowhere on the dash, as mine never had the lights installed.

Each of the fifty states has different rules regarding driving or fog lights, none of which seem to be enforced vigorously. Pretty much anarchy as to what you want to install. Just make sure that they don't blind an oncoming driver, or be so far out of alignemnt that you could be accused of shining deer.
R. L Carleen

IIRC there is one blanked switch position on the 66 cars - the main light switch moved to a pull switch and left the position nearest the ignition switch empty.

The parts list shows the fog / spot switches as "as required" so, yes there could be both types fitted - normally by the dealership rather than the factory.

Any additional switches were traditionally fitted to supplementary panel screwed under the edge of the dash, often with warning lights too.

Spots were always wired to only come on with main beams and fog lights to come on with side or dipped beams.

A double pole relay fitted would enable one switch to control both types of light depending on the position of the main beams.
Chris at Octarine Services

Chris:

Thank you as you've provided at least some information about the possible location of the switch.

On another Mg list, a responder said the switch (toggle)had two postitions, one for the fog and one for the driving lamp. However the wiring diagram doesn't show that one switch controls both devices. Nor does it show a indicator lamp

Yes, the wiring diagram shows the driving lamp(s) is connect to the low beam side of the the heads, and the the fog(s) is connected to the lighting switch. NO relays are shown.

<<<snip>>>
Just ditch the B and get on A
<<<snip>>>
I also have a mga twin cam. Is that good enough?

<<<snip>>>
Mine has a switch to nowhere on the dash
<<<snip>>>
All T series cars also had the fog lamp switch and wiring for future installation.

<<<snip>>>
I would assume it is the same in the States.
<<<snip>>>
Not in the state of South Dakota.
Blake


Bullwinkle

I believe US law requires that the headlights be on whenever fog/driving lights are turned on. Thus the through wiring.
Dan Robinson

"I believe US law requires that the headlights be on whenever fog/driving lights are turned on."

Laws of this type are done on a state-by-state basis, and the laws can differ by quite a bit from one state to another. Tennessee, for example, has no such law.
Dan Masters

This thread was discussed between 05/01/2005 and 06/01/2005

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.