Brake lights stopped working

[Donny_L]

Last night I was ejoying a nice joy ride until I realized my brake lights stopped working. The tail lights are okay but no brakelights when I step on the brake. What should I check first?

 

[AUSMHLY]

Hi Donny,
Check your break light switch.
Moss motors part number 111 on the diagram.

If you do find it's defective, some of us, me included, have replaced that style switch with a mechanical one. (Second photo) Here's a link to where I purchased mine, and a write up about why we go with a mechanical style.

https://www.watsons-streetworks.com/brake_switches.html

Good luck,
Roger

 

[Donny_L]

where do I find it on my 61 ah 3000? how do I check it? Im a poor machanic and even worse at electrical.

 

[Deleted member 8987]

One way to check it by yourself is to A) find it, B) unplug both wires, C) jumper the two together (paper clip should work...just don't let it touch anything), D) ignition on, E) get out and look at the brake lights.
If they are on, the switch is bad, replace it.
If they are not, come back for more troubleshooting.
Dave

 

[John Turney]

It will be on the inside of the right frame rail under the distributor.

 

[AUSMHLY]

It will be on the inside of the right frame rail under the distributor.

My switch is under one of my horns (1964 BJ8). These photos will show you what the switch looks like.

I'm running a mechanical switch, that's why you don't see the wires running to mine. My switch is now just being used as a plug.

Roger

 

[Keoke]

One way to check it by yourself is to A) find it, B) unplug both wires, C) jumper the two together (paper clip should work...just don't let it touch anything), D) ignition on, E) get out and look at the brake lights.
If they are on, the switch is bad, replace it.
If they are not, come back for more troubleshooting.
Dave

And this is the simplest way to go---Keoke-

 

[Donny_L]

Well I tried that and no brakelights. What's my next move guys? I sure was hoping it was the switch. I forgot to mention that my horn doesn't work either. I don't know if they went out at the same time but when I noticed the breaklights not working I tried to honk my horn at the heavens in frustration and nothing happened. Funny huh

 

[Keoke]

In the fuse box on the firewall is a 50 amp fuse at least it should be if original check and see if it is blown---Keoke

 

[Donny_L]

okay, one of the fuses is cooked but I think it's been for a while. The other one was just a bit loose. When I tightened it the breaklights came on while the wires were together and the horn works again. So my switch IS bad,right. Two questions; can I get one of these switches at the local part store? and are both of these fuses suposed to be 50 amp?

 

[Deleted member 8987]

No, the switch may be good if the feed supply was bad.
NOW, with the fuseholder fixed, re-connect the brake light switch, back the car up to a wall, ignition on hit the brakes, and see if the wall glows red.

Another thing I do every time I fire up one of my cars is ignition on, engine off, watch the ammeter (if so equipped) and nail the brake pedal.
If the ammeter dips, at least one light is working.

 

[Keoke]

okay, one of the fuses is cooked but I think it's been for a while. The other one was just a bit loose. When I tightened it the breaklights came on while the wires were together and the horn works again. So my switch IS bad,right.

Two questions;
1] can I get one of these switches at the local part store?

I doubt it these are British fuses "Lucas" . However, you can replace the 50 Amp one with an American fuse of the same physical size rated at a capacity of 35 Amp. OK.


and 2] are both of these fuses supposed to be 50 amp?

No originally one was a 35 Amp and the other was the 50 Amp

Equivalents UK to US Lucas Fuse Rating (British)
BUSS AGC Equivalent (American)
50---------------------------30 Americam
35---------------------------25 American

 

[Donny_L]

There's only 2 fuses. So witch one goes where? 30 on top and 25 on bottom? or the other way around?

 

[Donny_L]

Well I went to the parts store and the guy sold me a switch he said should work.When I took the old one out it leaked some brake fluid out. Since the switch is hydrolic it shouldn't work until I bleed the lines and get the pressure back up. Am I on the right track or did I just buy a $21 piece of worthless junk.

 

[Keoke]

There's only 2 fuses. So witch one goes where? 30 on top and 25 on bottom? or the other way around?
[/quote


Yep it's the other way around---- :laugh:

 

[Keoke]

Well I went to the parts store and the guy sold me a switch he said should work.When I took the old one out it leaked some brake fluid out. Since the switch is hydrolic it shouldn't work until I bleed the lines and get the pressure back up.

Well usually it is not necessary to bleed the brakes but at times it can be required.


Am I on the right track or did I just buy a $21 piece of worthless junk.

I am not sure just have to wait and see,never used anything but a known correct replacement part.--Keoke

 

[Donny_L]

Well now I got real trouble. When I went to top off the break fluid I noticed some nasty stuff floating in the resivour. It looked like snot or flegm. So i took off the res. and cleaned it real good,refilled the res with new clean dot3. Then I went back to bleeding the breaks. Some of that nasty stuff must have gotten into the lines and now my front left brake is locked up.NOW WHAT ????

 

[Keoke]

Well now I got real trouble. When I went to top off the break fluid I noticed some nasty stuff floating in the resivour. It looked like snot or flegm. So i took off the res. and cleaned it real good,refilled the res with new clean dot3.

Dut 4 would have been better.--- : :frown:

Then I went back to bleeding the breaks. Some of that nasty stuff must have gotten into the lines and now my front left brake is locked up.NOW WHAT ????

1] disconnect that brake line at both ends and blow it out with air and Pray.

2] You may have to do the same to the caliper with the pistons out----

 

[Bob_Spidell]

Donny,

DoT 3/4 can gel or crystallize, esp. if the car sits for long periods. If you see crud in the reservoir, the entire brake system may be contaminated. I doubt soft 'snot' would cause a front piston to hang up; there is probably crud on the caliper piston seal causing it to stick. This is an obvious safety issue; IMO you must inspect, clean and repair the system as required. At the least, you should empty the reservoir, break the connections at each wheel--and the master cylinder--and flush the system (might be a good time to replace the flex lines, too). I would use a flare nut wrench for this; most fittings on a Healey are 7/8" though IIRC there are some smaller ones on the master cyls. If you have a Harbor Freight in LV they have cheap flare nut wrench sets. I would flush first with denatured alcohol or brake cleaner, followed with copious amounts of air to dry everything. Inspect the fittings and the flare on the ends of the pipes. Any cracks or distortions on the pipe flares will cause you grief sooner or later. This would be the time to replace the switch if you still suspect it. Reconnect the lines--being careful not to cross-thread--and refill with fresh brake fluid. Remember, DoT 3/4 absorbs moisture from the air very quickly so get a new (quart or liter) bottle--and bleed the whole bottle through.

If this fixes the stuck caliper, fine. If not, you will need to pull that caliper and essentially rebuild it. If you do one, you should do the other, and the rear slaves as well.

Obviously, you can farm this job out (it will cost hundreds of dollars), or try it yourself. We all started as lousy mechanics (heck, I still am), but we kept at it. Allow yourself plenty of time to do the job, inventory the tools and parts you'll likely need and acquire them, think it through and be patient with yourself. If you have any 'mechanic' friends invite them over for a beer and subtly steer the conversation towards cars, like 'hey, I have this old Healey with brake problems, and ...'

 

[Randy Forbes]

You can get a good idea of what Bob's talking about, looking at the pictures I did of this MKIII.

Starts around here: https://www.rfdm.com/gallery/album201?page=31 but the meat of the job takes place several pages later, and goes on and on...