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bad short

i was putting the electrics back together in my 88tc and as i put the positive terminal on the battery the wires on the positive side of the terminal started smoking(big yellow, red/orange stripe wires).  i dont have a lot of things hooked but i think i missed a ground? would this happen if things under the dash arent connected? the steering column is out and all those wires are obviously disconnected.

bad short

Reply #1 –
Sounds like a short some where or the battery in backwards...

Disconnected circuits will NOT cause such a problem....

bad short

Reply #2 –
the battery is hooked up correctly...i have a short somewhere. i completely gutted the engine bay and completely removed the dash in an attempt to clean up the bay...the car ran before i did that so i know i've done something stupid.  The positive battery cable is hooked directly to the solenoid.  One negative cable goes from the battery post to the block, then to a ground, then to the 2 pr0ng connector. The other negative cable goes from the starter to the negative side of the solenoid.  On the positive solenoid i have the 2 small connectors attached( all the fusible links) and of course the small push on connector is attached( i marked the posts before i removed them).            With both the battery cables hooked up, as soon as i hook up the wire bundle with the lg yellow, sm yellow and red wire/orange stripe it arcs.
  I Ohms checked the wires coming off it and they checked normal (.o4 or so). i'm kinda stumped on this one.

bad short

Reply #3 –
Quote from: lakenheath24;217201

  I Ohms checked the wires coming off it and they checked normal (.o4 or so). i'm kinda stumped on this one.


IF you're getting .04 ohm to ground on the yellow wire with everything off, you have one Hellacious short...

bad short

Reply #4 –
Here"s how I would trouble shoot it:
Buy yourself a test light, They're cheap.
Remove the negative battery cable from the battery.
Hook the test light between the cable and the neg battery post.

You won't be cooking the wires with this setup.

Isolate the wires one at a time from the solenoid to see which one lights the light.
If more than one, follow the one that lights it the brightest.

Do you have EVTM wiring diagrams?

bad short

Reply #5 –
I ohms checked the wires from one end to the other with my Fluke meter, I didnt check them to ground.  O.L would mean a broken wire and low to zero would mean a short to ground?? I will get the exact ohms reading tonight. It was a long weekend...I put the entire drivetrain in this weekend(putting in a t-5 by yourself was a lot easier when i was 25)  plus hooked up all the wiring, radiator, power steering, etc.  By the time i hooked the battery up to check electrics I was pretty frazzled. Keep in mind the steering column isn't hooked up.
  Soft touch i could use those wiring diagrams please, thanks. I have a haynes manual and it's weak.  I will try your method tonight.  The thing is with those wires is that they are all hooked together via a fusible link...do i prick each one with a paperclip and touch it to the positive side of the solenoid?

bad short

Reply #6 –
What ground wire do you have connected to the solenoid??? The solenoid grounds through where it's bolted to the car and shouldn't be grounded to anything else.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

bad short

Reply #7 –
it's the negative cable going to the starter. I moved the solenid under the fender well, which your question just jogged another possibility. I secured it with 2 screws so it should be grounded but i'll double check that tonight also. thanks.

bad short

Reply #8 –
Quote from: lakenheath24;217297
it's the negative cable going to the starter. I moved the solenid under the fender well, which your question just jogged another possibility. I secured it with 2 screws so it should be grounded but i'll double check that tonight also. thanks.

Negative cable going to the starter???

Neg cable connects to the block and that's how the starter gets it's ground...

bad short

Reply #9 –
Here is my setup--I have 2 "negative" cables. one is a big funky thing with the battery terminal, a small ground, a connecor for the block and a plug that goes into the wiring harness.  The other cable goes from the negative side starter solenoid to the starter. Sorry if i wrote it confusingly. Did I do that wrong?!  I took a bunch of digital pics to help me remember how to put things back together but apparently that wasnt one of them.:D

bad short

Reply #10 –
There is no negative side on the starter solenoid... Positive connects to it and is fed down the cable to the starter... No there isn't voltage on it(except when cranking) and will measure low resistance to ground due to the internal resistance of the starter, but it is never ground...
 

bad short

Reply #11 –
rog, i always assumed pos and neg but i get it now.  so the wires that are shorting on the solenoid...i traced all the wires and the heavy yellow ones that go to the rectangle connector on the steering column
are brownish an inch or so back from the connector and the plug looks melted...i'll try and post a pick.  My thing is this connector wasnt even hooked up.  How does that thing melt? i can only assume the two wires were grounded? does anyone have a schematic of the steering column wiring.....

bad short

Reply #12 –
It's probably the ignition switch connector, and melting is common in them (so is fire, so make sure you fix it AND install a new switch). Still, even if the connector is melted it shouldn't short out unless it's touching ground.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

bad short

Reply #13 –
Does the insulation on any of the fuse links look like it got too hot?
If so, what color fuse link?

bad short

Reply #14 –
Quote from: lakenheath24;217147
i was putting the electrics back together in my 88tc and as i put the positive terminal on the battery the wires on the positive side of the terminal started smoking(big yellow, red/orange stripe wires).


1. On the positive terminal of your solenoid you should have a yellow wire that's spliced to six fuse links.

2. You should also have a green fuse link that's spliced to three wires; a yellow, a yellow/white and a red/orange.

Is group #2 where the short is? If so is the instrument panel sitting where the ammeter may be shorted to ground?