Unknown Switch ???

[George Zeck]

Hi everyone ....


In process of rewiring some vital items on the car // switching from positive earth to negative ground and we found what clearly appears to be a small black switch underneath the dash / immediately below & underneath the speedo. Since the car is in pieces now -- can't turn anything on.

Any idea's ??

(it's so hidden I want to say it's a "kill switch". Remember, clearly stock not aftermarket item).

Tx

George Zeck

 

[Biff]

The "unknown" switch is your panel (instrument) light switch. It (the panel lights) are either on or off. This is the same for bugeyes and both the Mk-II and Mk-IIA cars.

 

[Tullamore]

Speaking of unknown switches, my Sprite has a switch in the middle of the console directly above the steering column. I think it is called the brake switch, when you push it the red light comes on. What does it do?

 

[sockeyedsushi]

indicates you have brakes. it is a brake light failure switch. when you push the button you test the light.

 

[Tom Rynne]

To be a litlle more exact on the brake failure light, it is activated when one of the hydraulic circuits experience a loss of pressure due to leakage such as a rear cylinder seal failure or a damaged brake line. The brakes have 2 circuits for safety. If one fails you still have 2 wheels to brake.
The light is activated by a switch which in turn is closed by movement of a small piston inside the brass brake line junction on the inner fender. The pressure drop to one circuit under a leaking condition causes the piston to move to the side of lower pressure which causes the switch to be activated and the dash light to come on constantly thus warning you of the failure. This is not to be ignored!
Pressing the test button on the warning light is, as was stated above, only testing that the bulb in the light still works.
Bleeding the brakes can sometimes cause the piston to move and it must then be recentered.
I had the entire master cylinder on my 72 B siphon dry when the O rings on the piston failed. The cure for this is to remove the brass junction and clean it and the piston and refit new O rings. The junction seems to be a place where any crud which is present in the brake system tends to collect!

 

[spritenut]

The Brake failure switch.
It comes on when you step on the brake pedal and it goes to the floor.
Then you say Oh $h!* No brakes, but now there is a light on the dash to let you know this.