LS3 swap alternator wiring problems

[pt2285]

So I swapped to the LS3 for a few months now and I have a spear tech harness which has the pack connector into the alternator. I also have the single wire in my painless kit from when I had the SBC engine. So I plugged both in and ran it for past 3 months with no problem but little miles. Recently my voltage is jumping and running around 18.1 v and I’m seeing st the gauge and on my scan tool which is not good. So am I double feeding the system or did I fry the voltage regulator? Or do I just not have a wire jumping from the pack connector to the lug output to send signal to regulator?

[andrewb70]

How exactly do you plug in two connectors into an alternator that only has one spot for a connector? All you needed to do was use the plug on the Speartech harness. I'd take the alternator off and have it tested. Or, unplug the connector(s?) and see what the voltage output is. Without any connections the alternator will put out a constant 13.2-.4 volts.

Andrew

[parsonsj]

Sounds like you connected the alternator output lug to the signal wire, making the alternator charge full-bore all the time.

If that's true, you've bypassed the voltage regulation, which should be done by the ECM.

[pt2285]

Metric pack 4 connector in where it goes.. wire from post to starter where it goes... those are the connections.

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Sounds like you connected the alternator output lug to the signal wire, making the alternator charge full-bore all the time.

If that's true, you've bypassed the voltage regulation, which should be done by the ECM.
Metric pack 4 connector in where it goes.. wire from post to starter where it goes... those are the connections.

[andrewb70]

.....


Metric pack 4 connector in where it goes.. wire from post to starter where it goes... those are the connections.

Those are the right connections.

Andrew