• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

brake light circuit?????

Share this page

H

Healey_Z

Jedi Warrior
Offline
Can someone help me with the brake light circuit. They stopped working over the weekend. The running lights and turn signal still work correctly, just having an issue with the brake lights.

Looking at the schematic, power (G) to one side of the brake switch, the other side (GP) goes to the flasher relay, which I assume is to allow one bulb to work while braking and flashing at the same time. Is this a common part to fail? Where is it located on the car (1963)?
 
Hey Healey Z,
electrics are not my strong point so will let others weigh in on the circuits but you might check out the brake light switch. That is located on a 3 or 4 way brass T fitting on the passenger side of the engine compartment, down below about where the generator is mounted. Just follow your brake lines. I had a similar problem on my BN6 and was a bad brake light switch. You can get a replacement at places like NAPA and Moss and assuming you have a BJ7 ? so they might have a listing for it. You can take the old one off without having to bleed your brakes if you are careful and do not allow air to get into the lines. They are below the switch so do not touch your brake pedal until you get the new switch replaced. Put the new one in and you find real quick if that's the problem. I had a problem with the new aftermarket switches not sealing up properly so switched to a mechanical switch. If you end up with the same problem get hold of me and will get you the info on it.
Good luck,
Mike
 
Hey Hans,
Thank you, that is the exact mechanical switch I bought and using now plus the link tells how to check out the old one without taking it out, etc.
Regards,
Mike
 
You may want to check the 2 connections at the brake light switch, Make sure you are getting power there by using a ohm meter. I crossed them with the horn connections one time and my brake lights where always on! I would assume your 63 switch is the same as my 67. check the easy things first like bulbs and there connections as well.
 
My experience with the stock brake light switches is that as they age they begin to lose their responsiveness to light pedal pressure but they will still make a circuit when stomped on hard. This often makes it difficult to discover a switch that is failing as opposed to failed, especially if one is working alone.

While I normally install upgrades for parts and systems that are known to fail I find it a lot easier to replace the brake switch every couple of years than install a pedal mounted unit.

I guess I am getting unresponsive as well.
 
Hi HZ,

I agree that it sounds like a faulty brake pressure switch that should be replaced or an electric switch added.

A number of years back I was interested in wiring a ā€œroll-overā€ switch into my fuel pump circuit. When scavenging for the switch in the trunk of a late 70s Ford Crown Vic (the Ford had the switch behind the driverā€˜s side trunk panel), I found an electric brake switch that seemed to be new. Bringing both home, I wired in the roll-over and then created and fitted a bracket to the air plenum that positioned the switch in line with the edge of the brake peddle. The new switch was wired parallel to the original pressure switch so that original wiring to the pressure switch would be maintained and providing the benefit of having either switch to activate the brake lights.

Although the unit presented by Hans is one used by many, other units can also be scavenged and used at a very reasonable price (in most cases $0). In my experience, I have found the original pressure switch to be very reliable ā€¦.to a point of failure. The trouble is that it will fail and you wonā€™t know it. I suggest that, since the new pressure switch replacements seem to have a much shorter life span than the originals, all should install an electric brake switch as soon as possible. Since it is wired in parallel, it can easily be removed for a concourse event.

All the best,
Ray (64BJ8P1)

P.S. I also recommend the installation of a roll-over or interrupter switch on the fuel pump power connection as well.
 
P.S. I also recommend the installation of a roll-over or interrupter switch on the fuel pump power connection as well.

Yep and an inertia switch which shuts down all power is great too. Jags circa 1980 have them located in the " A " post
 
Michael

I do this in the garage with all garage lighting shut off you can then check the function of all your car lights right from the drivers seat.---Keoke
 
Well, you guys hit it on the head. I have to say that this fix was one of the easiest I've ever had. One of the leads on the switch had slipped off. Took me 5 minutes to find the switch and 5 seconds to put it back on :smile:

Thanks for the replies.
 
Healey_Z said:
Well, you guys hit it on the head. I have to say that this fix was one of the easiest I've ever had. One of the leads on the switch had slipped off. Took me 5 minutes to find the switch and 5 seconds to put it back on :smile:

Thanks for the replies.
Click to expand...

Nice when that happens....
 
Back
Top