Pontiac GTO Forum banner

1 - 20 of 29 Posts

·
Registered
Joined
·
114 Posts
Discussion Starter #1
So I just went to upgrade my old alternator battery charge cable to a 6 gauge to accommodate the 100amp alternator I put in.

I took the loom off and found 3 wires booger-soldered into the charge cable. It looks like they are part of the harness that goes to the firewall plug in for the fuse panel (left side)???

1. is this normal?
2. if so, how best to go about splicing these into a 6g cable more cleanly?

My worst skills are electric/wiring issues so any help GREATLY appreciated.

Thanks
 

Attachments

·
Registered
Joined
·
114 Posts
Discussion Starter #2
Following up, could it be the "stereo" guy that put a system in my car 15 years ago spliced into the charging wire for key-on power to the fuse fuse panel to power the stereo and amp?

If so, I could simply crimp on extensions to those wires and run them directly to the alternator stud with post connectors?
 

·
Registered
Joined
·
114 Posts
Discussion Starter #5
Ylw, Sure that wire is “key-on”and not “always on”?
Not sure, Jetzster...I assume power only comes from the alternator charge wire when it is spinning, but I may be wrong and it might be a circuit??

I've had a mystery power drain for a decade (had to instal a cutoff switch) so perhaps this is the source of it.

Not sure what those spliced wires are for.

I need to get the car running, so I'll probably just extend them individually to the alternator post until I can figure it out later...electrical is my weak link!
 

·
Premium Member
Joined
·
370 Posts
Not sure, but its likely that alt wire is always hot when the battery is connected..
Sounds like a plan ylw, you could just see what doesn’t work at all with them disc first , just for some helpful info later,if you have a Volt-ohm meter set it in current mode
on 2000 millamps or
( 2amps) or a higher scale is better , and then touch one probe on the +batt Term and the other probe to each wire for just a second, if the meter moves at all, then that particular wire is a drain On the battery..

As long as you extend them with same or slightly larger gauge size wires, All is good for the moment, you could use some barrel
crimp splice connectors and then put some ring connectors on the ends At the battery terminals bolts for now
 

·
Registered
Joined
·
114 Posts
Discussion Starter #8
ok, thanks guys.

I'm almost sure this was a kludged job by the stereo guys. since the alt charge wire is always hot, regardless of key-on, then it makes sense the stereo head unit/amp are the likely power drains.

Gonna route the wires as mentioned above, then do the detective work once the car is running again.
Thanks for all the help!
 

·
Premium Member
Joined
·
370 Posts
Ylw , later, You may need to add a couple 2-5A inline fuses To those 2 wires , that is , if there aren’t any now, which would have been another major wiring screw-up of those stereo guys,tieing those power wires in they way they did is an abomination 😱

and then you’ll need to find a good key -acc- or -on spot to tie them down , that should stop any mystery battery drains, sometimes they did that ‘always-on ‘ thing to keep ‘memory’ going in older after-mkt stereos..
bet that car is lookin Great man, post more pics when ya can😄
 

·
Premium Member
Joined
·
872 Posts
Hard to see from the photo but the factory did splice several wires into the charging wire. That big blob wasn't factory but the smaller splice below it may have, at one time, been a factory splice. Here are a few photos of a spare harness I have. The wires in the background attach to the Alternator.

tempImageFWbF12.png



tempImagepQDruf.png
 

·
Registered
Joined
·
114 Posts
Discussion Starter #11 (Edited)
Ylw , later, You may need to add a couple 2-5A inline fuses To those 2 wires , that is , if there aren’t any now, which would have been another major wiring screw-up of those stereo guys,tieing those power wires in they way they did is an abomination 😱

and then you’ll need to find a good key -acc- or -on spot to tie them down , that should stop any mystery battery drains, sometimes they did that ‘always-on ‘ thing to keep ‘memory’ going in older after-mkt stereos..
bet that car is lookin Great man, post more pics when ya can😄
Good suggestion. I actually need a "key on" port for my new electric fan relay, but all the "accessory" ports in the under dash fuse panel are occupied by stereo system stuff...which is weird, because I think the spliced wires lead to those ports on the fuse panel (same side harness plug as the side of the panel). Any other key-on places to pull power from?

There are under dash fuses between the panel and the stereo accessories.

Also, I cannot find any clipped wires as evidence that the original harness was cut and spliced. super weird :unsure:
 

·
Registered
Joined
·
114 Posts
Discussion Starter #12
Hard to see from the photo but the factory did splice several wires into the charging wire. That big blob wasn't factory but the smaller splice below it may have, at one time, been a factory splice. Here are a few photos of a spare harness I have. The wires in the background attach to the Alternator.

View attachment 139567


View attachment 139566

Wow, good to know. Any idea what those splices were for from the factory (options?)?
I don't feel good about anything being directly spliced to a 6g alternator wire!
 

·
Premium Member
Joined
·
370 Posts
Weird wiring, have to check it out later for sure,
I believe The ‘wiper ckts Buss fuse’ is usually 20A Key-on and It’s that’s a pretty robust size fuse , Which prob is the best place to pull from ,so then need to find the feed to the wiper motor on it’s ‘drop’ side to 3m half-tap into , under dash, to pull from for the fans,from there, they will need their own smaller size inline fuse in this as well.
 

·
Premium Member
Joined
·
872 Posts
The splices go to the various power supply components; Horn Relay, Starter, Firewall fusebox plug, Voltage Regulator.

Depending on year, you'll find similar splices for the headlight circuit, under dash battery/ignition feeds. They'll be wrapped in heavy black tape under the regular harness tape.


BBBBDAE3-A0E8-4BDC-AB68-32ACA1965936_1_201_a.jpeg
 

·
Registered
Joined
·
114 Posts
Discussion Starter #15
The splices go to the various power supply components; Horn Relay, Starter, Firewall fusebox plug, Voltage Regulator.

Depending on year, you'll find similar splices for the headlight circuit, under dash battery/ignition feeds. They'll be wrapped in heavy black tape under the regular harness tape.


View attachment 139573

fascinating, I had no idea.

in my car none of these wires go anywhere except to the plug in the firewall behind the fuse panel.

to make things even more complicated, my car has a mini starter (installed because I had too many no-starts from headers overheating stock starter solenoid) wired up with a Ford external starter solenoid on the fender....

I installed a cut off switch to resolve the drain, so basically what I need to know now is the best place to get "key-on" power for the SPAL fan relay kit.

Someday I'll redo it all with a Painless harness...
 

·
Registered
Joined
·
114 Posts
Discussion Starter #16
Weird wiring, have to check it out later for sure,
I believe The ‘wiper ckts Buss fuse’ is usually 20A Key-on and It’s that’s a pretty robust size fuse , Which prob is the best place to pull from ,so then need to find the feed to the wiper motor on it’s ‘drop’ side to 3m half-tap into , under dash, to pull from for the fans,from there, they will need their own smaller size inline fuse in this as well.
the dual fans require individual 35a inline fuses, so I think I need a stand alone port or...
 

·
Premium Member
Joined
·
370 Posts
Wow, I forgot they do need a lot o juice,

Well then, maybe you’re gonna need a double-pole 40-50A relay mounted up front ,
then You will have to tie one of its two off-on-contacts into the always -on power right off the battery ,
then the other relay contact to a frame ground,
all that done with 8-10ga wire likely right at that big 12v terminal block near the horn relay,
then you’ll run its smaller load winding control wires to the ‘key-on’20A wiper ckt under the dash,that way the relay handles the big fan load with its 35a fuses to the fans in-line ,
but u would have its control winding on a key-on ckt, At your command to shut off ,

But! Likely some electric fans I think are just “direct wired” to the ‘always on’12v block so the fan can cool and run off and on awhile after u shut the car off, as much as it wants
then they Would use their own thermostat/timer -relay- built in that finally shuts em off, you’ll just have to see what kind of controllers your fans may use to know how to hook em up..it’s all fun stuff😆
 

·
Registered
Joined
·
114 Posts
Discussion Starter #18
Wow, I forgot they do need a lot o juice,

Well then, maybe you’re gonna need a double-pole 40-50A relay mounted up front ,
then You will have to tie one of its two off-on-contacts into the always -on power right off the battery ,
then the other relay contact to a frame ground,
all that done with 8-10ga wire likely right at that big 12v terminal block near the horn relay,
then you’ll run its smaller load winding control wires to the ‘key-on’20A wiper ckt under the dash,that way the relay handles the big fan load with its 35a fuses to the fans in-line ,
but u would have its control winding on a key-on ckt, At your command to shut off ,

But! Likely some electric fans I think are just “direct wired” to the ‘always on’12v block so the fan can cool and run off and on awhile after u shut the car off, as much as it wants
then they Would use their own thermostat/timer -relay- built in that finally shuts em off, you’ll just have to see what kind of controllers your fans may use to know how to hook em up..it’s all fun stuff😆
Thanks.
The wiring diagram from the relay kit is very simple and I'm set on all but where to hook up the 2 "ignition" wires. This and the alternator charging wire SNAFU are the only things separating me from starting the car! eager to get it done
 

Attachments

·
Premium Member
Joined
·
370 Posts
Got it,so they’ve got a temp sender that you got to put In a block port (somewhere) , putting a ground on the relays windings as needed to run the fans, and an overide
Switch to run them if you want more cooling,

Could just put the two big 30A leads at the first stop the 12v positive battery cable terminates at , usually that’s the block at the horn relay,

Like ya said, They Seem to want ‘ignition key-on’ power for the two relay windings in series..

(so going to that 20A wiper ckt Wire at the fuse box would work, and also let ya get the engine going, I’d just clip a small alligator jumper wire off The wiper fuse’s drop side for now anyways , and then run it to the ‘ign’ wire)

no fans with the key off ,will be the case that way,

if you went ‘always- on’ with that ‘ignwire hooked with the 2 big fuse wires , the battery would be at the mercy of the sender unit round the clock , with or without the engine running to charge the battery, prob wouldn’t
Run too much after awhile, but it would be a bummer if the battery got affected by it
 

·
Registered
Joined
·
114 Posts
Discussion Starter #20
So I got the fan relays and larger gauge alt charge wire done last night.
Also butt-connected the three previously spliced wires to individual wire with ring terminals for the alternator stud.
I'm still not certain what they are for, and now am thinking direct hook up to a 100amp alternator where it used to be stock 55amps is gonna cause an issue?
 
1 - 20 of 29 Posts
Top