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Discussion Starter #1
Hey guys, I've been doing some well needed work to my Cougar and I finally got around to buying a solid state sequential unit and a new brake light switch. I hooked them up and everything was okay. I tested everything and it all check out fine. Then, the second time I went to start it, the ignition switch fell apart (cheap Oreilly crap) so I bought another one and replaced it, a procedure I've done many times before.

I tried to start it, and it first appeared that the battery was dead, so my brother came by to give me a jump, and it started smoking profusely!!! Never happened before, so I figure it has something to do with the ignition switch, sequential unit or brake switch. The smoke was coming from a burnt wire that runs into the distribution block and into a cluster under the dash. My 3G alternator fuse (175 amp) blew as well.

1. would the alternator fuse stop the car from starting?
2. Would a reversed brake light switch wire cause that distribution block wire to burn?
3. Why am I getting no power to anything?

Thanks guys, this is my daily driver.
 

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Did you let all the smoke out of the wires, or did they just get warm? It sounds like your ignition switch wasn't entirely seated, and something got crossed. so in my opinion,
1. No
2. No
3., to be determined.
Is the battery still good? Does it have 14.5 volts in it? Are you familiar with a "voltage drop test"?
Will the car try to start at all, or is it like having no battery at all? Battery power to the starter motor is the "low voltage" side, to turn the engine physically. Voltage out to the distributor, to fire each idividual cylinder, "high voltage" side. Depending on how bad your wiring now is, the car may not run at all. Can you post a picture of the damamge?
 

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Discussion Starter #3
My camera has been acting up so no pics man. The battery is reading 12 volts right now, I'm confused as to what would have caused such a catastrophic failure. Whats is that wire coming from the distribution block called anyways? the car acting like they're is no battery at all. Maybe that alternator fuse has been gone for a while and it finally killed the battery. But if I'm getting a voltage reading there should at least be the dome lights coming on right?
 

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Discussion Starter #4
well as it appears, the wire that burned was the brake warning lamp switch wire. It seems like it might have been exposed and touched some metal somewhere and blew the alternator fuse in the process of a short circuit. I'm going to take the battery in for testing at the local auto shop while I try to figure out this wiring issue I guess
 

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By "distribution block", are you talking about the fuse box, under the dash? "IF" the wiring harness has melted together inside, then you now have lots of wires touching each other, when they should not. Pictures would help, as we can't see what you are looking at.
IF the car was running fine, until you changed out the ignition switch, then it seems reasonable to start there with the diagnostics, as to what went wrong...
 

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Discussion Starter #6 (Edited)
okay here are the pics, maybe the ignition switch is defective, I went and bought some batteries for my camera so here are the pics...The black wire that comes out the side of the ignition switch burnt up as well as the brake warning lamp switch wire. The harness is fine thankfully, no other wires were singed.

ignitionswitchburnt2.jpg This is the brake warning lamp switch wire

ignitionswitchburnt3.jpg heres the burnt wire here (drivers side vent)

ignititonswitchburnt.jpg heres the new ignition switch with the black wire disconnected, it was burnt and the burnt wire goes all the way up into the thick cluster of wires. What caused this is beyond me. Maybe the ignition switch is bad?
 

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Discussion Starter #7
so apparently that wire that goes to the Brake warning lamp switch wire burned. IT goes from the ignition switch through the harness and into the engine bay were it leads to the brake warning lamp switch (which doesn't work) Thats seems odd other than the ignition switch acting crazy. I'm sure the battery drained down from the alternator fuse being blown. But I think the ignition switch is defective though from what I can see so far.
 

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Sure sounds like something is shorted...? Looking at my 69 diagram book the dual brake warning switch (HARNESS 14290 has wipers/washer/alt regulator) has a feed from post of the ignition switch (po=violet) might be diff on a 67 though. (or it is to burned to see real color?) Could be a bad switch maybe...what about leaving off that connector and see what you have? Blowing that big alt fuse is cause for concern.....
 

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Discussion Starter #9
That alternator fuse doesnt blow easily so I know that the short had something to do with that. The wire is purple in my car too so I dont know why it would short out. It's not on the same circuit as the stop lamp switch or sequential unit (thank goodness) so I'm guessing this ignition switch is faulty. Why it burned up is beyond me. I assumed that the brake warning lamp switch would activate with low pressure. It just started smoking as soon as I went for a jump from my brother. Maybe that blew the alt fuse?
 

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Discussion Starter #10
update: I went to Oreilly to have the battery tested and it tested bad, so I bought a new alternator fuse, and I'm going to exchange the ignition switch and buy a new battery and we'll see what happens then. The only link between the alternator and brake warning lamp switch is the switch so I pretty sure now that's the culprit. Everything was fine until I changed that switch out.
 

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Makes sense - but just in case don't smoke another battery - leave yourself a way to quick disco it if needed
 

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Discussion Starter #12
Thanks guys for all your suggestions and help, I got another ignition switch and battery and everything is back to normal (except for the burnt wire) Do you know what that purple wire leads to? One goes from the side of the ignition switch and two wires split, one goes to the brake warning lamp switch and the other I'm not sure of. I didnt hook it up so I wanted to make certain it doesn't cause any more trouble. But I like to have everything hooked up, any wiring diagrams I can check out online, the one in the haynes manual sucks.
 

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My 69 diagram shows it as a violet resistance wire which runs to a connector to the dash pannel - which feeds through teh warning lights (oil/brake/alt) and then has a return side through the constant volt regulator
 

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Discussion Starter #14
okay thanks I'm going to end up buying a wiring harness from Ron Francis in a few months, so I'm going to rewire anyways, I just wanted to know if it was something that would stop me from being able to drive the car.
 

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Well, adapting a harness isn't going to be a walk in the park either - honestly I'd dig deeper into it with a schematic in hand, or see if Johns/WCCC has a good one you can get. I have a 69 diagram book - but I think youd want a 67/68 if anybody has one. I could send you some scans this weekend if need be? PM me if ya want em....
 
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