1 wire alternator install problem.

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aclever1
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1 wire alternator install problem.

Post by aclever1 » Fri May 17, 2019 9:48 pm

I can't get it to charge! I bought a second alt just to make sure it wasn't the first alt that was bad but its still not charging, My amp gauge is in the neg and when lights are one its at -15. Its a new battery, I checked ground and eveything looks good. I drove around the neighbor hood and gave it a few minutes a few blips of the throttle and the amp gauge stays in the neg.

I've had electrical problems for a while, battery draining and somethimes it wouldn't start and then a few seconds later it would just fine. It's a new starter too. I had the electric tested and they kept telling me it was the voltage regulator so I've got through 3 of them to test but kept having problems. I got a new battery and it boiled over and so I decided to replace the alt and battery but I can't get it to charge and with it running it stays at 12.3v.

Do I need to unhook the old voltage regulator? and how do you hook up the dummy light?

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Nissanman
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Re: 1 wire alternator install problem.

Post by Nissanman » Fri May 17, 2019 11:12 pm

Haven't had experience with this conversion but I would suggest the 1 wire jobby is INTERNALLY regulated so you don't require the OEM external regulator.
Nissanman, just trying to help.
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JT68
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Re: 1 wire alternator install problem.

Post by JT68 » Sat May 18, 2019 5:53 am

I've found about 50% of the ebay "1-wire" Denso's won't actually function as a 1-wire. You probably need to add a switched 12v line to it. - I believe that goes to the upper terminal of the little T connector, but you should confirm that.

The most convenient source is the black/white wire that goes from the ignition switch to the regulator.
(If working on the right side, it is right there at the regulator connector, if working on the left, you would need to cut into the harness to find it)
I bet if you add the switched 12v line it will charge.

It should be a switched IGN+ line, or the regulator will always be powered and draining your battery.

Nissanman is right, the old regulator serves no purpose, you can disconnect it and remove or leave it there for aesthetics. No reason to leave it connected.

Hope this helps! J
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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 12:48 pm

I hooked a wire from the alt #1 to the black/white wire that went to the regulator and It might have been working, amp gauge was at 0 when running but dropped to about -5 when lights were on but when I turned the key off the car continued to run.
Last edited by aclever1 on Sat May 18, 2019 12:55 pm, edited 1 time in total.

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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 12:54 pm

I was reading that I might need a diode on that wire is that correct? and is there a certain diode I need?

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datsunrides
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Re: 1 wire alternator install problem.

Post by datsunrides » Sat May 18, 2019 1:47 pm

What type of alt is this? GM or? Generally a 1 wire alt uses a wire directly from the battery and depending on the alt, a wire off that to “excite” the internal reg.
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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 4:21 pm

The one thats on now is a GM 81 camaro alt, the first one is unknow but looks very similar to this one. I wired it with a inline 30 amp fuse on the main power wire that was connected to the old alt. Then terminal 2 is looped back to the batt post on the alt. I added a wire from terminal 1 to the black/white wire from the regulator wire but the car kept running after the key was tuned off. I checked that black/white wire and it was a switched ign wire so wierd that the car kept running.

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nismou20
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Re: 1 wire alternator install problem.

Post by nismou20 » Sat May 18, 2019 5:42 pm

The single wire GM will need a blip/throttle to start the charging. When you first start engine it will not be charging. Also terminal 1 wire not needed for charging. I think it’s only used for idiot light if you desire. Try disconnecting white wire and see if engine will start/charge after blip.

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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 6:16 pm

I have blipped the throttle and even driven around for a few minutes, it never shows it charging. it's alway about -3 to -25 amps on the meter and my voltage is never above 12.6.

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nismou20
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Re: 1 wire alternator install problem.

Post by nismou20 » Sat May 18, 2019 6:22 pm

Good ground on Alt/block/Chassis?

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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 6:41 pm

I have 3 ground wires to the frame right there that all use the same bolt in the frame, one to the neg battery, one to the alt and one to the block. The block one is questionable, the wire is connected to the bolt that goes to the alt bracket so it's not touching the block directly just the bolt that goes into the block but it's a new clean bolt. I also have grounds on the starter to the frame and the one that goes from the wire loom by the washer tank to the frame.

I just checked voltage and the main wire that goes from my wiring to the alt has .9v when the car is off. When started it stayed at .9 until I reved the car and then it went to 17v but at the battery it was only 12.4v. Still negative ohms on the gauge though.

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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 6:46 pm

I tested again and this time between 1v and 3v when the car was started and 16-17.5v after a rev.

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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 6:48 pm

I thought these were internally regulated and it's weird the amp gauge is negative.

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nismou20
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Re: 1 wire alternator install problem.

Post by nismou20 » Sat May 18, 2019 6:58 pm

I’m assuming the old external reg out of the equation?

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aclever1
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Re: 1 wire alternator install problem.

Post by aclever1 » Sat May 18, 2019 7:19 pm

I have it unplugged but still in the car.