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Discussion Starter #1
Red wire on the back of the radio has "IGN" tag on it. I understand this is the one that supplies power when ignition is "On" or "Acc". The other one (yellow) is connected to the battery to keep the clock running... no problem there.
I had the last radio's IGN (red) connected to yellow/black which also is supplying power to an aftermarket gauge or two... can't remember exactly, been so long since I wired them.
Anyhow, when I test continuity to the yellow/black wire and dash metal I'm getting continuity. I had a positive wire from yellow/black and a ground running into the trunk to power a sub-woofer.
The sub didn't work and the wires were heating up, so I shut everything off and tested continuity. Both leads signaled continuity when I tested against my tail light housing.
I pulled the wire all the way up to the dash when I found the + connected to the factory yellow/black wire. The - was grounded under the dash.
Is there a different wire I'm supposed to be using, or is that yellow/black wire defective or shorting out somewhere? The aftermarket gauges all work the way they're supposed to and they're connected to that y/b wire.
 

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Discussion Starter #3
I have mine attached to the ignition post. Power is only supplied when the key is on.
Do you mean the pigtail on the back of the switch? Which wire?
I think, when I installed the gauge... tach or temp, I was instructed to connect it to the Y/Bk, but I don't see one on the pigtail.
 

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Discussion Starter #7
How about the original radio feed wire?
When I bought the car, one of the POs had replaced the factory radio with a Craig cassette deck. I used the same wire for the power supply on my last radio, but that's the one I'm having issues with (Y/bk) and I'm now wondering if that's what killed it.
When I tried it for the new radio, it worked fine, but I also get continuity when I test it against dash metal, so I'm looking for an alternative.
it was the same wire I tried to use to power the sub in the trunk, but the wire got hot, I got that funny ozone smell, and the sub didn't work.
I have the dash off and I'm planning to remove the instrument cluster so I can see the back of the ignition switch. I can get my hand back there and I can't feel the "post" that Mr. Hangar is referring to.
Looking at the pigtail I posted, any suggestions on which wire (if any) would be appropriate?
 

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When I bought the car, one of the POs had replaced the factory radio with a Craig cassette deck. I used the same wire for the power supply on my last radio, but that's the one I'm having issues with (Y/bk) and I'm now wondering if that's what killed it.
When I tried it for the new radio, it worked fine, but I also get continuity when I test it against dash metal, so I'm looking for an alternative.
it was the same wire I tried to use to power the sub in the trunk, but the wire got hot, I got that funny ozone smell, and the sub didn't work.
I have the dash off and I'm planning to remove the instrument cluster so I can see the back of the ignition switch. I can get my hand back there and I can't feel the "post" that Mr. Hangar is referring to.
Looking at the pigtail I posted, any suggestions on which wire (if any) would be appropriate?
God only knows what PO has done to wiring but generally main power (red lead) feed +12V supply goes to ACCESSORIES on ign switch position (& terminal) & On some Stereo units with an extra colored poet feed lead often with a Tracee is can often b for a built-in Automatic Power Antenna UP & Down relay added extra, wired to either Ign on or Accessories too..
OR you can take an entirely new separate FUSED DIRECT 12V power feed from a know full time power terminal source, like the " Hot" feed wire to Ign switch direct from the Battery BEFORE it goes through the Ign switch, particularly if you want independant of the drivers key, full time on/off function.
Have good earths, use a head unit tail strap (metal bracket off back of unit, to take out any shake) & for any Aerials if not glass embedded make sure a good earth is used & keep leads short as poss to reduce Ignition noise.
Before powering ABYTHING UP CHECK ACROSS 12V IN & EARTH/METAL CHASSIS FOR ANY SIGN OF SHORTS OR LOW IMPEDANCE (UNDER 3 OHMS - GO BUY A LOW COST ANALOGUE MULTIMETER EX TANDIES ETC).
GOODLUCK
Trev
 

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Discussion Starter #9
God only knows what PO has done to wiring but generally main power (red lead) feed +12V supply goes to ACCESSORIES on ign switch position (& terminal) & On some Stereo units with an extra colored poet feed lead often with a Tracee is can often b for a built-in Automatic Power Antenna UP & Down relay added extra, wired to either Ign on or Accessories too..
OR you can take an entirely new separate FUSED DIRECT 12V power feed from a know full time power terminal source, like the " Hot" feed wire to Ign switch direct from the Battery BEFORE it goes through the Ign switch, particularly if you want independant of the drivers key, full time on/off function.
Have good earths, use a head unit tail strap (metal bracket off back of unit, to take out any shake) & for any Aerials if not glass embedded make sure a good earth is used & keep leads short as poss to reduce Ignition noise.
Before powering ABYTHING UP CHECK ACROSS 12V IN & EARTH/METAL CHASSIS FOR ANY SIGN OF SHORTS OR LOW IMPEDANCE (UNDER 3 OHMS - GO BUY A LOW COST ANALOGUE MULTIMETER EX TANDIES ETC).
GOODLUCK
Trev
I could connect the radio to the yellow constant 12v, but the sub in the trunk doesn't have an On/Off switch.
Do you (or anyone else) know which wire on the pigtail will work for power when Acc/Ign is on?
If not I'll maybe just put a toggle switch to turn the sub on and off.
 

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I could connect the radio to the yellow constant 12v, but the sub in the trunk doesn't have an On/Off switch.
Do you (or anyone else) know which wire on the pigtail will work for power when Acc/Ign is on?
If not I'll maybe just put a toggle switch to turn the sub on and off.
Which wire pigtail would have 12 volts on it ? Boy that would be bear impossible without wiring diagrapm/Schematic to hand etc & why I said pick yourself up a low cost Analogue meter readout multimeter ex Napa, Autozone etc & do some testing yourself - unless you want to put your self in hands of a shop, you'll have to zero in a little closer.
NB some stand alone units had a Feed/Hot power take-off to run an accessory sub : it should be labeled if so.
Make sure you are aware of ALL pitfulls & fish hooks before attempting full wire-up, as it sounds like you may've given your Sub Amp a fright already ?.

You can always do a 'Bench test' wire up & test before ib-car install & hook up.
Cheers.
 

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Which wire pigtail would have 12 volts on it ? Boy that would be bear impossible without wiring diagrapm/Schematic to hand etc & why I said pick yourself up a low cost Analogue meter readout multimeter ex Napa, Autozone etc & do some testing yourself - unless you want to put your self in hands of a shop, you'll have to zero in a little closer.
NB some stand alone units had a Feed/Hot power take-off to run an accessory sub : it should be labeled if so.
Make sure you are aware of ALL pitfulls & fish hooks before attempting full wire-up, as it sounds like you may've given your Sub Amp a fright already ?.

You can always do a 'Bench test' wire up & test before ib-car install & hook up.
Cheers.
How many amps does the sub need? Easiest solution would be to put a relay to power the sub to avoid too much load on the ignition feed circuit and switch the relay using an ignition "on" source.... off the fuse box... YEL to the heater, GRN to the Seat Belt Warning Lamp and BLK/RED to the backup lamp/NSS switch are hot in ignition "ON".
 

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Discussion Starter #12
Which wire pigtail would have 12 volts on it ? Boy that would be bear impossible without wiring diagrapm/Schematic to hand etc & why I said pick yourself up a low cost Analogue meter readout multimeter ex Napa, Autozone etc & do some testing yourself - unless you want to put your self in hands of a shop, you'll have to zero in a little closer.
NB some stand alone units had a Feed/Hot power take-off to run an accessory sub : it should be labeled if so.
Make sure you are aware of ALL pitfulls & fish hooks before attempting full wire-up, as it sounds like you may've given your Sub Amp a fright already ?.

You can always do a 'Bench test' wire up & test before ib-car install & hook up.
Cheers.
I have a digital meter. It's a nice one. It's what I used to figure out which set of wires went to the power and the speaker in the trunk... and to test my charging system... and to see if I shut the correct breaker off when I'm changing a plug in my house... and when I have to do electrical service on an illuminated sign. :)
 

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Discussion Starter #13
How many amps does the sub need? Easiest solution would be to put a relay to power the sub to avoid too much load on the ignition feed circuit and switch the relay using an ignition "on" source.... off the fuse box... YEL to the heater, GRN to the Seat Belt Warning Lamp and BLK/RED to the backup lamp/NSS switch are hot in ignition "ON".
NSS would be perfect, seeing I swapped over to a T5, so that connection is available. Thanks!
 

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I have a digital meter. It's a nice one. It's what I used to figure out which set of wires went to the power and the speaker in the trunk... and to test my charging system... and to see if I shut the correct breaker off when I'm changing a plug in my house... and when I have to do electrical service on an illuminated sign. :)
Well then, USE it on the Install wiring measuring voltages !...
Drip-fed info helps no-one.
(But I've heard & seen it all b4)

Goodluck: this 3rd Generation Technician/Install Pro is tapping out.
Cheers.
 
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