SAAC Forum

The Cars => 1968 Shelby GT350/500/500KR => Topic started by: RSOHC on July 11, 2019, 05:33:24 PM

Title: Emergency Brake Warning Light
Post by: RSOHC on July 11, 2019, 05:33:24 PM
I have installed the instrument panel and there is a warning light illuminated indicating that the emergency brake is on.

The warning light is near the right turn indicator and the unused seat belt indicator.   

Did I install a light bulb in the wrong hole or should there be an electrical fitting installed without a light bulb? 

If there is a switch for the emergency brake, where is the switch located ?

Lauran
Title: Re: Emergency Brake Warning Light
Post by: Krelboyne on July 11, 2019, 05:56:45 PM
E brake switch is clamped onto the emergency brake tube. Here is the bare switch. Single wire which completes the ground.
Title: Re: Emergency Brake Warning Light
Post by: Coralsnake on July 11, 2019, 07:14:32 PM
Sorry, that switch was not used (from the factory)

There is no "emergency brake" indicator in the 68 dash.

There is a light that says " brake" but it refers to your entire braking system, not the emergency brake.

If the light remains on, then your brakes are not properly proportioned and must be re-bled.

The "belts" light was not used on 68 Shelbys. That indicator requires extra wiring and a relay.
Title: Re: Emergency Brake Warning Light
Post by: RSOHC on July 30, 2019, 11:32:52 PM
I have completed the bleeding of all of the brakes and the brake light in the instrument panel is still on.   Is there a special procedure for bleeding the brakes?  I did the front brakes first and replaced all the fluid in the system with DOT 4. 

Lauran
Title: Re: Emergency Brake Warning Light
Post by: mr68shelby on July 31, 2019, 02:33:59 AM
Hi Lauran.

Unplug the wiring harness from the plastic switch on the brake distribution valve. It has two wires that are purple with white stripes.

If the light goes out, the problem is either in the switch or the piston in the distribution valve that activates the switch. If it stays on, the problem lies elsewhere. The piston has to be centered or it activates the light. The valve is designed so that a front or rear brake failure will cause the piston to move due to the unbalanced pressure. When bleeding the brakes this same thing can occur.

And if I remember correctly, I had a problem with a new switch when I did my brakes a few years back. Seems like the plunger was too long and activated the light even when the piston was centered.

If the piston is not centered there is a procedure in the service manual to center it, but I don't remember what it is offhand.

Mike

Title: Re: Emergency Brake Warning Light
Post by: shelbydoug on July 31, 2019, 07:38:23 AM
You need to reset the plunger by pressing it in manually.
Title: Re: Emergency Brake Warning Light
Post by: Coralsnake on July 31, 2019, 08:48:24 AM
The procedure is in the 1968 Mustang shop manual.

The posts above are correct, the piston is not centered in the distribution block. Unplugging the sensor will cause the light to go out, but will not resolve the issue. 
Title: Re: Emergency Brake Warning Light
Post by: Bob Gaines on July 31, 2019, 11:28:26 AM
  Use this Proportion Valve Bleeding Tool when bleeding your brakes to lock the prop valve in place and keep the valve from tripping of center.
you simply remove the warning light switch (white plug) on the valve, then screw in this tool while bleeding your brakes.
After the bleeding process is finished replace the warning light switch.   https://www.ebay.com/itm/proportioning-valve-bleeding-tool-PV2-tool-new/331577706194
Title: Re: Emergency Brake Warning Light
Post by: shelbydoug on July 31, 2019, 01:14:53 PM
Did they have a "emergency brake on" warning light? I don't remember ever having that? I must be deprived...or is that depraved? Huh?
Title: Re: Emergency Brake Warning Light
Post by: RSOHC on July 31, 2019, 02:03:39 PM
will the bleeding tool work if the valve is already out of position?

Lauran
Title: Re: Emergency Brake Warning Light
Post by: Coralsnake on July 31, 2019, 02:21:42 PM
There is no "emergency brake" indicator in the 68 dash.
Title: Re: Emergency Brake Warning Light
Post by: shelbydoug on July 31, 2019, 02:26:36 PM
Quote from: Coralsnake on July 31, 2019, 02:21:42 PM
There is no "emergency brake" indicator in the 68 dash.

So the flashing lights are for something else? ;D
Title: Re: Emergency Brake Warning Light
Post by: Coralsnake on July 31, 2019, 02:31:08 PM
Ask the doctor to adjust the meds down?
Title: Re: Emergency Brake Warning Light
Post by: Bob Gaines on July 31, 2019, 02:53:25 PM
Quote from: RSOHC on July 31, 2019, 02:03:39 PM
will the bleeding tool work if the valve is already out of position?

Lauran
You have to get it centered first . If you do it hydraulically then you will have to force it one way or the other by bleeding a front or rear and then look down the switch hole for the groove the switch or pin tool sits in before installing the pin to bleed the brakes.  You may have to do that mechanically because sometimes they get stuck and will not move.  They can be tricky to stay centered while doing the bleeding which is why the need for the tool . When redoing a brake system for example it is very easy to get one off center and the simple tool saves time and aggravation.
Title: Re: Emergency Brake Warning Light
Post by: 1967 eight barrel on August 06, 2019, 12:55:32 PM
That has nothing to do with the "emergency brake". It's the bias light that tells you the distribution block pin is not centered. Could be the brake master, a leak which caused the light to come on. Also, the ignition switch also functions as the system proof light to function. I had an ignition switch fail that caused mine to stay on. There is a tool that also will hold the pin centered while you bleed them once you center the valve. Your seals may also be damaged in the brake distribution block. I can link you to the tool if you'd like.
                  -Keith