HELP! Magic smoke related December 30, 2005, 04:58:29 PM Background: my daughter left the lights on overnight in my '88 and ran the battery down. To make a long story short, my neighbor tyring to be helpful, jumped in and hooked up the jumper cables before I could get out of my truck that I had pulled up to jump the cat. Needless to say, said neighbor had the polarity reversed when he hooked up the cables. My first indication that something was amiss, was a large amount of magic smoke excaping from the general area of the coil cover. I jumped out of my truck and yanked the cables off while proceding to ask my nit wit neighbor if he was color blind. Upon surveying the damage, I found one thourghly smoked two into one fusable link, which of course nobody has. I replaced the link with a couple of weather proof in-line fuses, so they are now good to go.Now we get to the current problem, everything works EXCEPT for the radio, dash lights, and fuel pump. I have checked all the fuses (all good), the fuel pump relay, and most of the fusable links that I can find.Sooooo, does anybody have any other ideas on where I can look for a problem? TIAEdited to add that the key was on if that makes a difference. Quote Selected
HELP! Magic smoke related Reply #1 – December 30, 2005, 09:13:06 PM Wow, Sorry to hear about that mishap.:hick: You probably still have some fried wires/links. Looking at a wire diagram (for a 5.0L) shows the main power feeding three fuse links16 Ga black link - goes to Black/Orange wire, powers engine compartment light, rear defrost, and dash lights etc.20 GA blue link - goes Black/Orange wire to EEC power relay20 GA blue - goes to Yellow wire to fuel pump relayThere is also a separate green 14 GA fuse link that goes to a couple black fuse links that providesd power to the hazzard lamps & other stuff.How about checking to see if you have power at the engine compartment lamp, EEC power relay ( by EEC), and fuel pump relay on those color wires (Blk/O, Blk/O, and Yellow)I found the Help section at the auto store had some generic fuse link wire. Quote Selected
HELP! Magic smoke related Reply #2 – December 30, 2005, 11:26:17 PM Magic smoke heh hehI thought you couldnt replace fuseable links with fuses? Quote Selected
HELP! Magic smoke related Reply #3 – December 31, 2005, 12:36:20 AM just use those inline ato holders Quote Selected
HELP! Magic smoke related Reply #4 – December 31, 2005, 04:11:06 PM Thanks for everybody’s suggestions. Here’s the carnage list:One fusible link who gave it’s life in a vain attempt to save the rest.One fried ECU, I guess it didn’t want to swing both ways.One toasted alternator, see comment about ECU.One inoperable stereo head unit, I’m hoping that the in-line fuse took the hit instead.Lesson learned, hook up your own cables when jumping a dead battery!!!Yea magic smoke. ;) A friend of mine who is into electronics explained it to me this way. When every electronic componet is made, it is made with a little bit of magis smoke inside that makes it work. And if you hook something up wrong, or overload it, the magic smoke excapes and the part will no longer work.:D Quote Selected
Need some electrical help please Reply #5 – January 01, 2006, 05:23:31 PM For the back ground see my magic smoke thread. http://www.foxtbirdcougarforums.com/showthread.php?t=6222Now my alternator is blowing the 30 amp fuse that I used to replace the fusable link about two seconds after I start the car up. Should I replace the in line fuse with a fusable link? Quote Selected
HELP! Magic smoke related Reply #6 – January 01, 2006, 06:08:11 PM Inline ATO fuse holders are only good for 30 amps, and marginally at that. The design of the ATO fuse makes it not work well with any higher amperages - the contact area between the blades of the fuse and the clips in the fuse holder is not enough for higher amperages (I know you can get 35 amp ATO fuses, but I recommend against it).That being said, if your alternator's output is going through the fuse (or fusible link) you definitely need something higher - even the stock 65A alternator will easily melt a 30A fuse. I'd recommend installing either OE-spec fusible link or a large capacity aftermarket fuse & holder (such as the type you see in "stereo cars").If it's the field feed of the alt that is blowing the 30A fuse your alt is baked. The field (the part of the alternator that is controlled by the regulator) should only draw a few amps - 15 at the most, and that would be during absolute full-tilt output. If you're drawing more than that the rotor in the alternator is shorted to ground.BTW, just a FYI - a rotor can test perfectly good on the bench but have a short on the engine. It's called a "Flying short" or "Dynamic short" and I had it happen on the last 3G I had on the car - it kept eating up brushes & springs. Turns out that as the alternator spun the rotor would expand with centrifugal force. The expansion would be enough to reveal the short, and would then cook the brushes and holders. Take the alt off the engine and open it up and the rotor would test good. I went through about 4 sets of brushes before finding that one... Quote Selected
HELP! Magic smoke related Reply #7 – January 01, 2006, 06:32:24 PM MN12 batteries go in 180-degrees relative to Foxes. I learned this the hard way. Luckily the only thing I fried was a few fusible links. Quote Selected
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