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*HELP!* New Radio Smoking at dash!

jteck10

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9:27 PM
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Help! i keeps blowing fuses when i connect the battery.
Heres a synopsis of what happened

car was working and running fine
i wanted to replace my old radio with a new one (link to new radio)
i first took out my old dash bezel, and gauges, since i had to move them from the old bezel to the new one. i put everything back and installed the new radio
like a dummy i was doing this all with the battery connected
i connected the radio power, then reconnected the red and black wires to the ammeter in the back that were there (wires touching gauge housing before the washers)
while i was trying to wiggle it back into place i was scraping the steering column a bit with the back of the gauges
i also noticed all my dash lights were on at the same time, even with the door closed. the lighting knob wouldn't turn them off
i then undid the negative battery power so i could install the harness to the back of the gauges
after the harness was in and everything was tightened, i re-connected the negative side of the battery
i noticed smoke coming from under the dash inside the car and from the engine bay, so i undid the negative to the battery again.
i noticed there is a 30A fuse just after the voltage regulator (yellow in pic below) that was blown
i undid the power to the radio, replaced the 30A fuse, and tried to reconnect the negative terminal to the battery - it blew again
i undid the wiring harness to the back of the gauges, replaced the 30A fuse, and tried to reconnect the negative terminal to the battery - it blew again

did i fry the voltage regulator? (yellow in the picture below)
what is the black piece under the yellow voltage regulator?
are the red/black ammeter wires touching the gauges housing?
is there a part of the back of the gauges maybe touching the frame of the dash?

my finger is pointing to where the 30A fuses go

I'm not sure what the smoke was coming from and not sure where to even start checking

Any idea what to check/replace?

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Couple of things that I see here. First, don't know why you would connect radio to the ammeter because that receives full power from the battery and is always hot, much better to go to a battery accessory fuse.
Second, what you seem to be calling the voltage regulator is the starter relay, what also gets full vehicle power. I'm also not sure why you would have a voltage regulator fused.
The smoke from the dash may have been the instrument voltage limiter or the gauges, what are designed for 5.5 volts. There are fiber washers that go on the ammeter posts before you attach wiring, and if these are missing, bad things happen.

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60-69 voltage regulator
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70 up voltage regulator

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Instrument voltage limiter

Mark
 
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You hooked the red and black wires from your new radio to the 2 posts on the ammeter? That wouldn't be a good thing to do....
 
Couple of things that I see here. First, don't know why you would connect radio to the ammeter because that receives full power from the battery and is always hot, much better to go to a battery accessory fuse.
Second, what you seem to be calling the voltage regulator is the starter relay, what also gets full vehicle power. I'm also not sure why you would have a voltage regulator fused.
The smoke from the dash may have been the instrument voltage limiter or the gauges, what are designed for 5.5 volts. There are fiber washers that go on the ammeter posts before you attach wiring, and if these are missing, bad things happen.

View attachment 156975660-69 voltage regulator View attachment 156975770 up voltage regulator

View attachment 1569758 Instrument voltage limiter

Mark

sorry i might have explained that wrong. i didnt connect the radio to the ammeter, i re-connected the black and red wires to the ammeter that were on it when i took it off.
i didnt fuse the stater relay, it came that way - should i replace that?
i ordered a new insturment voltage limiter to replace that
i have those washers, and i installed the wires touching the base of the gauges, the washers next, and the nut on top. does the washer need to be touching the gauge housing instead?

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You hooked the red and black wires from your new radio to the 2 posts on the ammeter? That wouldn't be a good thing to do....

no, i might have explained that wrong. i didnt connect the radio to the ammeter, i re-connected the black and red wires to the ammeter that were on it when i took it off.
it does have washers, and i installed the wires touching the base of the gauges, the washers next, and the nut on top. does the washer need to be touching the gauge housing instead?

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This is a 67 ammeter. You can see the fiber washers insulate the housing from the wire. Wires directly touching the housing would be bad. It would be like hooking the wires directly together.

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This is a 67 ammeter. You can see the fiber washers insulate the housing from the wire. Wires directly touching the housing would be bad. It would be like hooking the wires directly together.

View attachment 1569820

i'll bet this is my problem then

i connected the wires under the washers, before the nuts - so they're touching the base

i'll redo as on top of the washers before the nuts

do i need the extra nut touching the washer? or can i get away using just the one nut on top?
 
Maybe you should think about bypassing the ammeter. Here's one post about it but you could search the site for more info.

 
i'll bet this is my problem then

i connected the wires under the washers, before the nuts - so they're touching the base

i'll redo as on top of the washers before the nuts

do i need the extra nut touching the washer? or can i get away using just the one nut on top?

I would just go to the hardware store and get a couple nuts & washers. And check the fiber washers to make sure they aren't broken/cracked.
 
It would be like hooking the wires directly together.

Correction here. What i said above isn't correct. But without the fiber washer you're still grounding out the connection.
 
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Correction here. What i said above isn't correct. But without the fiber washer you're still grounding out the connection.
i got what you meant, i'll redo it later today and see what happens

the fiber washers on there arent broken or cracked, so i'll try to reuse them
 
You should use two nuts on each post. The top nut tightens against the bottom nut. If you don’t have the bottom nut you’ll compress the washer and you might end up shorting the wire to the gauge housing again.
 
You should use two nuts on each post. The top nut tightens against the bottom nut. If you don’t have the bottom nut you’ll compress the washer and you might end up shorting the wire to the gauge housing again.
got it, i'll add another nut under the connection
 
I wouldn't try to hunt down where the smoke came from too. Maybe bulkhead connection?
 
Swapped the washers and wire connections and she works just fine! now i'll try to look into bypassing the ammeter sometime soon

thanks again for all the help!
 
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