Oh $H!7 Something popped (electrical) car died and smoked, won't crank now

Discussion in 'Fox 5.0 Mustang Tech' started by criticman, Mar 30, 2006.

  1. Use the test light with the ignition switch in the run position. Any good ground will do. As you said, stab both sides of the fuseable link.

    As part of your testing , you might want to look for 12 volts on the red injector wires. Do this with with the ignition switch in the run position. No 12 volts and you have either a failed EEC relay or blown fuse link.
  2. Thanks! I'll get down to this tonight and post up results - hopefully good news, but any progress is progress I guess.
  3. Eagerly waiting until I get off work, I browsed Advance Auto Part's website and found the only test light listed...for $10.99. Pic is below. Any other place I should try or particular brand that is going to be $3 (or at least cheaper than the AAParts one)?

  4. Found this on O'Reilly's website:
    Part No: 66316

    So I guess I will check them out first, then I can hit up Advance Auto Parts if the O'Reilly part looks like crap.

    Wish me luck. Will post later how the testing goes.
  5. The one pictured above is fine, they do have cheaper models out but it may not last as long. I have a Craftsman personally...
  6. Since I'm shadetree, I get test lights at Harbor Freight when they're 99 cents. Nothing of quality, but they work alright for me (I'm not a professional like Rick, who needs good, reliable tools).

    Whatever one you get, bench test the light with the ground you're going to use before you begin - it's irritiating to have a test light that doesnt work, or having it attached to a bad ground point (so it never lights up).

    Good luck.
  7. Well, TMOSS was right about the price - $2.99 @ O'Reilly's Auto Parts.

    Looks good to me:
    View attachment 463202
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    Good point HISSIN - I'll make sure it works before I test it out on something that may or may not be working properly.

    Now if the stupid rain would stop...don't think testing electrical problems in an open carport with the battery/starter solenoid side of the stang right at the edge of the roof cover is the smartest move.
  8. I have received several request to post up a recap...so here it is from the middle of page 3, plus some new items (in bold):

    To review the situation:
    • something blew/popped, smoked when hood closed
    • isolated cause: wire on MAF connector was being cut by metal it was rubbing against and in closing the hood was last bit it needed for the wire to be exposed to the fenderwell opening metal
    • 14ga fusible link for Charging Circuit appeared to be fried...not positive, but replaced it anyway.
    • I taped up the MAF wiring and it is secure. Car still will crank but not turn over because fuel pump is not priming. The PMS is now receiving some power from the EEC as it lights up and it has black lines across the screen.
    • I have tested the 18ga fuel fusible link off of the starter solenoid...no resistance across is, so continuity is fine and that fusible link did not fry.
    • Tried the fuel pump test by grounding the pin in the EEC test connector - nothing happened
    • Did the "reset" of the collision fuel cut off in the hatch
    • Tried pulling codes with Actron code scanner - it gives a static noise/light, so it is not properly pulling codes
    • EEC does make a clicking noise when you turn the key.
      [*]Battery died after a couple of months of sitting since this happened, but have a brand new one in there, ready to go
      [*]Tested voltage at collision/inertia switch - Dark Green/Thin Yellow had 1.91V, other wire had none. This was with key in and in the on position, tested using multimeter prong (positive; negative was on chasis ground), in each of the connector's ports.
      [*]Bought a test light, and am going to re-test each of the fusable links, both before and after the fusable area.
      thanks to TMOSS et al for suggesting this method in addition to the previous multimeter test
  9. GOT IT! ... maybe?

    Posting up the LONG details now...
  10. Alright...here goes...note the colors are as best as I could tell, due to aged wires and tight spaces.

    First, I tested the light to make sure I had a solid ground by tapping it on the positive battery post...then again on the positive side of the starter solenoid:
    View attachment 463108
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    View attachment 463110
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    Then I started going wire by wire (no key in ignition yet), testing before and after the fuse link. Some pics:
    View attachment 463112
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    View attachment 463114
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    View attachment 463116
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    Until I found one that would not light. Then I tried it with the key in and on...still no light.
    View attachment 463118
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    View attachment 463120
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    So, here is the chart:
    (Green = Test light lit up; Red = No light)

    Starter Solenoid
    --->Green 14GA
    ------->Fuse Link
    ------->Split (maybe fuse link, not easily seen, taped up, didn't feel like link)
    ------------>16 GA Fuse Link
    ------------>16 GA Fuse Link
    ------------>16 GA Fuse Link
    ------->18 GA Fuse Link
    ------------>Light Orange(?)

    ------->20 GA Fuse Link

    So, I am about to go through TMOSS's chart/diagram to see what that wire is, but feel free to beat me to it and reply!
  11. 20ga Blue is the EEC primary power source and the power for the injectors, every sensor, MAF and fuel pump. Found it all on your own..........

    Learned something today?!
  12. Heh, yes sir I did - it was fun...sickening to even say that, but it was, lol. Hmm, so that tiny little wire is what powers ALL of that. Well crap.

    So, what would you advise doing? I mean, it looks like that blue wire meets up top with the brown wire before connecting to the ring terminal for the positive side of the starter solenoid.

    What part of it needs to be replaced? Is the splitter from the ring terminal to the blue/brown a TINY fuse link?

    I guess that is why I am still a bit confused. Not sure why the wire has no power before or after the link (unless since it is so tiny I am sliding the piercer right by the wire, although I did try it numerous times at various angles...
  13. You have to identify where the link is burned and cut that section out - or replce it from the ring back to the point where the wire is burned up. Use that new tool to find where that is.
  14. Awesome. I think for sake of how tiny it is and how easily it will turn to swiss cheese, I will just replace it from the ring to the fuse link on to where it connects the the main wire (which I think looked yellow). That way I will know that circuit will be new and should be good to go.

    Man I hope that is it!
  15. Here is probably a stupid question: do I need to tape up the pierced wires with electrical tape? Or is the pinhole piercing made by the test light too small to worry about?
  16. It's a good idea to put a little dab of silicone on the wires where you probed them. It will do a better job of sealing out moisture than tape will. Most people don't bother, but it will help prevent corrosion inside your wiring
  17. Any particular kind of silicone since there is such a variety?
  18. I just use some clear Permatex RTV
  19. The one color Permatex I don't have, lol. I'll need to hit up the store for the fuse link wiring, so I'll pick up some clear Permatex.
  20. Personally I would probably go with Liquid Electrical Tape. I think it bonds better to wire insulation than RTV and won't rub/peel off. It is also temp/solvent resistant and comes in a few colors. The one drawback is that it is a bit messy to work with. I would also use it to replace the electrical tape you have wrapped around the MAF wiring.