Relay burned up

[paulr]

Per driver common sense, I perform a safety system check every other week. Last night turned up no brake lights. Tail lights ok, turn signals (which use the brake filament) are ok. So the lights weren't compromised. Fuses are ok. The relay looked like this...

...and the plug is destroyed...

I have rebuilt, replaced, restored everything myself, so this is an unexpected problem. A year ago I bought the '64 optional relay/harness (Bird Nest $100) and had no problems till now. This car had NO relay from the dealer, and worked for 49 years without it--I should have left it alone.

Can't really be a short, or otherwise the turn signals wouldn't light. I'm lacking experience; is this how relays normally die? Doesn't look right. Should I just replace it and cross my fingers, or is there a root cause I need to diagnose? Thanks.

[wabigoon]

Just changed mine over to that system, hope it does not do the same thing, that's what it's suppose to stop.

[redstangbob]

I'm guessing the burned wire on the end is the hot wire? If the relay is a Chinese re-pop, it wouldn't surprise me that it failed internally. I'd wire in a Bosch type and hide it behind the washer bag. JMO Bob C

[Tbird100636]

I have 2 cents to add to this conversation, but not now. Let's just say I had a similar failure...

[Tbird100636]

Well, here's my story. Our 64 Bird was one of the ones that slipped through the cracks and didn't get the brake light recall done back in the day. Taking a proactive approach, I ordered the repro. relay kit from the Bird Nest and installed it a little over 2 years ago. (When we first had the Bird in the late 90's the brake light switch did start to burn up from age and the heavy load, we replaced the switch and I would later replace the connector which seemed to work ok.) It was a rather complete kit, only missing the solder in connector necessary to hook it up, which the Bird Nest sent a used one. It did look like a decent quality kit, install was easy, and it worked. Fast forward to almost 2 months ago. I was just getting back from a show and backing our 64 into the garage. I did not see the usual reflection of the brake lights on the back wall of the garage and found out the brake lights hadn't been working. I didn't hear any clicking from the relay when stepping on the brake.

2 days later, armed with a test light, a special jumper I made to jump out the brake light switch connector, and another jumper I made for relays I started diagnosing the issue. So I jumped out the switch first. The lights worked and the relay clicked. OK, let's just make sure the switch is working... it was, plugged it back in and the lights worked. Damn, now it's working again... Knowing others had relay issues I jumped out the switch again and started the car up. I figured maybe the relay is getting hot over time, so left it jumped a few minutes. Much to my chagrin, nothing happened. I shut the car off, then tried repeatedly jumping and un-jumping the switch connector. Well it worked, went from a distinct click to a faint click, and no brake lights. The brake light relay was getting warm too. Just to be sure, I disconnected the relay and jumped the hot B+feed to the load (brake lights) and the brake lights worked. Checked the switch output to the relay and the ground circuit, both good. Bad relay. Now, my relay didn't get really hot and discolored, but the connector rubber was partially melted around the load terminal and the B+ terminal.

So instead of rolling the dice on another repro relay, I went to my tool box at work and grabbed an ISO relay setup (some here are calling it a Bosch relay for some reason). I used a larger variety ISO relay used for blower motors and radiator fans, complete with it's own connector. All I had to do was crimp on some blade terminals to plug it in place of the old style relay and it was set. Included are the pictures of what I found and the fix I did.

[redstangbob]

I went to my tool box at work and grabbed an ISO relay setup (some here are calling it a Bosch relay for some reason).

https://www.google.com/search?q=bosch+r ... PgodxWUNUw

https://www.google.com/search?q=iso+rel ... 8&oe=utf-8

Doesn't really matter what you call them, Google is your friend

[paulr]

I always heard Bosch-type or Bosch, but now I've learned something new; there's a lot of good info on this thing.

My Bird Nest harness and switch seem solid enough, but since the molded plug seems beyond reuse, I just decided to find the pigtail that matched the new relay. Trouble is wherever you get one of these, they have wacky wire colors--on this one the ground is blue? I could wrap it in black tape, make it little less random looking.

FWIW, counting the two '64 repop relays on this page, that makes four '64 Birds I know of burning out this way. Maybe they're all not bad, but four is a lot.

[OZZY Stewie]

Hi all,
Stewie in Aus. our 64 Tbird has been in our care for 6 or so years and was an electrical nightmare. It was not fitted with the brake safety relay. One day we were out on a cruise and returned home, put her in the garage and closed the roller door. About an hour later I went into the garage and noticed the brake lights shinning on the door and when I looked at the engine bay I saw smoke coming from the brake light switch. It was stuck on, burnt and cracked. The MC was completely drained. Put a new switch in the next day and all good but started to think that 6 brake lamps at 21W must be drawing a lot of current. After talking to my electrical mates at work and showing the 64 wiring charts we worked out that she needed a relay.

I went one step further and fitted two, one for the left and one for the right. Just behind the battery I installed a BUSBAR. I took power from there across in front of the radiator to the relays mounted behind the wash bag. (All new wiring) At the bottom of the steering column I cut the two wires that go from the turn signal switch and wired them to relays (trigger) The output from the relays is wired to the two brake light power wires that I cut previously and of cause the fourth terminal is earth. They work great. Foot on the brake both relays operate, L or R flasher on, one will operate on and off. I have five relays fitted and all are fused. (30A) The other 3 are Ignition, and left and right headlights, one low beam and one for high.

But I went one more step further and fitted a mechanical brake light switch to the brake peddle. First I fitted a 57 Tbird switch which lasted one month, burnt out because I think 57's are 6 volt. What a dummy!!! got a universal switch, made up a mounting bracket and fitted that. Now when I put the brakes on the peddle moves 1/8" and the lights are on long before I have brake pressure. This is what you need in modern traffic. Because I am always paranoid about brake lights I also fitted two (tinny) LED lights with chrome bezels to the chrome trim that runs under the gauges over to the passenger side and down to the console. These are wired to the two brake wires at the bottom of the steering column (the two wires from relay to brake lights). So brakes on both light up, turn left or right and one will flash, put foot on brake one is steady and the other still flashing. Sometimes my turn signal switch in the column does not completely cancel but I saw it move, I look at the two LED lights and they tell if there cancelled or not.

It took about 3 years to get her reliable (turn key) the PO have butchered so much wiring. An example, the reverse lights were wired up as flashers.
All the wires at bottom of steering column cut and all connecters gone. Those press together wire connecters everywhere. It when on and on.
Sorry for the long post, hope it helps somebody.
Have fun, Stewie in OZ

[paulr]

But I went one more step further and fitted a mechanical brake light switch to the brake peddle. First I fitted a 57 Tbird switch which lasted one month, burnt out because I think 57's are 6 volt. What a dummy!!! got a universal switch, made up a mounting bracket and fitted that. Now when I put the brakes on the peddle moves 1/8" and the lights are on long before I have brake pressure. This is what you need in modern traffic. Because I am always paranoid about brake lights I also fitted two (tinny) LED lights with chrome bezels to the chrome trim that runs under the gauges over to the passenger side and down to the console. These are wired to the two brake wires at the bottom of the steering column (the two wires from relay to brake lights). So brakes on both light up, turn left or right and one will flash, put foot on brake one is steady and the other still flashing. Sometimes my turn signal switch in the column does not completely cancel but I saw it move, I look at the two LED lights and they tell if there cancelled or not.

HI Stewie!

Questions:
Did you disconnect the pressure switch, and therefore run the brake circuit off the pedal-mount switch alone?
Do your interior LED indicators work with turn signals only (without brakes)?
Got any pictures? Thanks.

[OZZY Stewie]

Hi paulr, Yes the brake pressure switch is not used anymore. The two lights tell you everything. Coming to an intersection and you apply the brakes both light up and you put say left flasher on the left light flashers and the right light stays on. Take foot off brake and right brake light goes out and left still flashers until cancelled.
Will post photo soon when I learn to post them again. Haven't posted in a couple of years.
Also I fitted an ANL 60 amp fuse in the harness on the passenger side inner fender. That's the main power to fuse panel and to amp gauge. When I took the dash out 3 years ago the amp gauge was about to catch fire. I took it out and fitted a volt meter.
So having relays (fused) takes a huge amount of power away from the dash and an ANL fuse for the remaining power that does go to the dash should be covered in case of a major short. You see I have read many posts on this site on Tbird fires. We have had two cars catch fire in our club. One was a Mustang, the other a Corvette.
Pictures soon I hope. Have a great day.
Stewie in OZ

[stubbie]

Come on Stewie posting pics is easy as 1, 2, 3.
I'd be interested in seeing that as I don't think my bird has had any relays changed in it's time and it would be good to get some of the power away from the dashboard.

[Tbird100636]

I always heard Bosch-type or Bosch, but now I've learned something new; there's a lot of good info on this thing.

My Bird Nest harness and switch seem solid enough, but since the molded plug seems beyond reuse, I just decided to find the pigtail that matched the new relay. Trouble is wherever you get one of these, they have wacky wire colors--on this one the ground is blue? I could wrap it in black tape, make it little less random looking.

FWIW, counting the two '64 repop relays on this page, that makes four '64 Birds I know of burning out this way. Maybe they're all not bad, but four is a lot.

Yeah my ISO relay has the correct connector/pigtail, since my repro. relay connector wasn't to far gone, I went for simplicity and just did crimp on terminals to plug into the repro. plug. If worse comes to worse, I'll cut the repro. connector off and solder and heat shrink the wires.

[OZZY Stewie]

Hi paulr, here are the photos finally.(I hope.)

This is the busbar fitted near starter solenoid.

These are the 3 relays for head lights and ignition.

ANL 60 AMP fuse L/H inner fender.

Two relays for brake lights hidden behind washer bottle.

And another shot.
Stewie in OZ

[OZZY Stewie]

Well got some posted but #@* about. Sorry.
Stewie

[s1nemesis1s]

Hey Guys,
So I am going through my car and doing some rewiring. I am learning as I go. My car has been hacked up electrically, you would not believe some of the systems they installed or literal copper wire to bridge connections.

Now, I am learning a GREAT deal about relays - and I am experimenting. II would like to upgrade my relay for the horns, stop lights, etc to the newer ISO or bosch style. My problem is this, and it is one of ignorance...hoping you can educate me. How do I know what pin does what on these old relays? Which wire should go to 30, 87, heck even 87a! Is there a multimeter test? I know I can find switched sources for the input and so on, but figuring out what the rest should be can be a mystery. II would LOVE to get them all in a relay waterproof box and even fused as well.

In addition, I will be building a new fuse box as mine is broken and jb welded back together in spots - so understanding how to upgrade the relays would help in this too.

I know this is a big as, but I would appreciate it so much.