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Old 04-04-2020, 09:04 PM   #1
Malicious
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Alternator/wiring issues in LS swap 74

Hi all,

I have installed a 2003 ls1 from a local Australian commodore. This should be similar to the first year gto and potentially the early Camaro. It has a two pin alternator.

I am having issues with the alternator or the wiring for it.

I have wired the top white wire to the new constant power bus bar IÂ’ve installed ( IÂ’ve removed the old two post unit on the fire wall). The bottom brown wore I have hooked up to the existing brown alternator wire that goes through the firewall to the ignition switch. I have cut and wired in a 3v t10 globe into this wire between the firewall and ignition switch for an indicator light and added resistance as this is what I have read the alternator needs to avoid burning out.

Everything seems to be running great, engine and the alternator is charging the system, but the alternator light will not illuminate.

ThatÂ’s my first issue.

Second issue: while trying everything to work out wtf is going on I noticed with the battery connected the alternator got warm. After talking to a couple of mates I decided to replace the alternator as the seems to be a lot of people saying that indicates the diodes are stuffed.

After replacing the alternator with a new one, the new alternator is also getting warm(I donÂ’t think as warm however) and the light is still not illuminating.

Can someone help me work out wtf is going on?

Cheers!
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Old 04-05-2020, 12:20 AM   #2
layinrocker65
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Re: Alternator/wiring issues in LS swap 74

http://67-72chevytrucks.com/vboard/s...d.php?t=668938

This could possibly be useful for you
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Old 04-05-2020, 01:25 AM   #3
Malicious
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Re: Alternator/wiring issues in LS swap 74

Thanks!

I have read that before and that’s what I’ve followed for the install but I can’t get that light - wired in as noted- to illuminate!

No idea what I’m doing wrong. Starting to wonder if the alternator is wired up differently to the older style?
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Old 04-05-2020, 01:44 AM   #4
hatzie
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Re: Alternator/wiring issues in LS swap 74

Around 2002-2005 or so GM started to phase in PCM controlled charging. I'm not sure when the Holden division started to do that.
You could have an AD series alternator that's expecting a charge control signal from the PCM.
If you have it wired up as a self exciting self regulating alternator like the old SI and CS series that may be part of your problem.
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Old 04-06-2020, 05:48 AM   #5
Malicious
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Re: Alternator/wiring issues in LS swap 74

Quote:
Originally Posted by hatzie View Post
Around 2002-2005 or so GM started to phase in PCM controlled charging. I'm not sure when the Holden division started to do that.
You could have an AD series alternator that's expecting a charge control signal from the PCM.
If you have it wired up as a self exciting self regulating alternator like the old SI and CS series that may be part of your problem.
Thanks for the idea. Looked into it. Apparently it is not computer controlled.

Any ideas what’s going on?
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