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Discussion Starter #1
I brought the fastback home from my engine builders this morning, he replaced the leaking rear main seal and tuned it for me. This was the first time I've had it on the highway and it drove pretty good! Anyhow, my turn signals weren't working. I discovered that the fuse block has a bunch of corrosion in it and I don't have any power coming into the fuse holder for the turn signals, B/U lights, etc. I tried cleaning the contacts but no luck. It looks like I'm going to have to cut the old fuse block out and graft in another one. It oughta be a big PITA since the interior is in and it's difficult to get up under the dash to do any work. I'll leave extra wire coming out of the replacement fuse block so I can get to it better. I sure hope this is the last issue I have with it for a while.
 

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Welcome to the world of old Mustangs. Chances are, this will not be the last issue you have with it for awhile. The car is nearing it's 40 year mark (if it is a 70) and Mustangs were not known for quality when originally manufactured.
 

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Doug, Sorry to hear about another issue. You don't really have to cut out the old block and splice a new one, the contacts work just like some push on's. There are retention pins on both sides of the contact and you can push them out. If you have an old harness with the block you can use one from it.

If you don't let me know, I have an extra and I can remove the pins you need and I will send them to you. Mike
 

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Discussion Starter #5
I did try a metal brush on it when I was first doing the wiring. That didn't cut it so I even brushed on acid to dissolve the corrosion. That did work but apparently it's drawn moisture from the air and it's rusty again. I looked at the back of the fuse block and all the connectors back there were corroded too. As I was probing the back of the block to see if I had power on the wires coming in (I did), I got my finger burned on one of the other fuse holders. It looks like the corrosion is causing enough resistance that it's creating a bunch of heat so I guess if I don't replace it I run the risk of starting a fire.
Has anyone replaced the fuse panel by splicing the wires and did it work fine afterwards? I have two spare harnesses with good fuse panels so I'm planning to cut one of those out and use it. I really don't want to try to replace the whole harness now and the spares have had some of the wiring cut anyhow.
 

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Discussion Starter #6
Mike I looked at the fuse holders and didn't see how they could come out. It looked like they were riveted in. I don't see any retention pins, where do you access them and do they push out the back or front?
 

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From the front side you can push a small jeweler scredriver on each side of the contact and push it out the back. I just did it on my 67 and it works fine. The pins are next to the vertical portion of the contact on each side. I found I had to use two screwdrivers to remove them.

The rivets are only on those contacts that have a jumper strap and they don't go through the block.
 

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Would these help also...new fuse holders. Part number 14A068-1A, page 154 in the on line NPD cat.
 

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Discussion Starter #9
OK I see what you mean now. I was able to remove the fuse holder out through the back on one of my spare harnesses. I really don't think that will help me though as the holders will still have to be cut from the wires and new ones spliced in. They are corroded bad enough I don't think they can be saved and will just continue to rust.
 

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Discussion Starter #12
So I was able to push the fuse holders through the back of the block, clean them up as best I could with a die grinder and used dielectric grease on them to make a good contact. I had to splice one connector in when it broke off at the crimp on the wire. After putting it all back together I hooked up the battery and had power on both sides of the fuses for the turn signals and also the interior lights which didn't work either. I tried the turn signals and they still don't work. I've got power at the fuse, the T/S switch was just replaced, and all this stuff worked before I took it for a rear main seal replacement and tune up and I drove it home today.
Any ideas?????? I'm stumped.
 

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Bad ground somewhere? If it worked before, it's unlikely it's a part failure.
 

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Get out the schematic and follow where that power from the fuse box should go. I think it runs on an orange and yellow wire to the turn signal flasher, then the turn signal switch. Do your brake lights and/or emergency flashers work?
 

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Discussion Starter #15
Possibly I've lost a ground I suppose but I don't know how that would've happened...
Pete, my brake lights work but no emergency flashers, and the screwey thing is the interior lights don't work anymore either and they're on a seperate fuse which has power on both sides of it also. The backup lights don't work either and they are fused with the turn signals.
 

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In working the fuse box, you may have stretched some wiring and dislodged some plugs. The interior lights look to be run thru the headlight switch. I would check the headlight switch plug and any other plugs close to your work area.
 

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Discussion Starter #17
I just looked under the dash and couldn't find anything unplugged or loose but it's possible I'm overlooking something. The headlights and tail lights work. This is so frustrating. Thanks for the suggestions and if anyone thinks of anything else please let me know.
 

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Check for a short to ground in the circuits that don't work. The heat you described sounds more like a short than a resistance problem.
 

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Discussion Starter #19
I just checked the wire at the connector on the back side of the fuse block that supplies power back out of the fuse for the T/S circuit and there is no power coming through. I have power on both sides of the fuse on the front side so apparently the corrosion is keeping the circuit from being completed. I think I'm right back to my original idea of cutting the wires and splicing in a good fuse block with non corroded terminals. I'm just gonna go jump into it and hope it works. I'll update when I'm finished.
 

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Good luck.......
 
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