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2005 Chevy Uplander LT electrical trouble

2005 Chevy Uplander. I have tested the altinator, got a new battery. Then went and tested my fuses with it off and half of them light up and even some where no fuse should be anyone know what my problem is

First Describe your problem. Half of what lights up? Do you have a CEL on? Tested my fuses with “it” off, what is “it”?

Then there are the basics: what are we dealing with: Mileage, transmission type, engine size.

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Ok so here is everything that is going on with it. While driving lights flicker inside and outside the SUV. I tested the altinator, it came back fine. Someone told me to test my fuses with it off so that I could tell which ones had power going to them. But like I said about 10-12 light up with the power off to the SUV. So will you be able to tell me what might be going on. I really need help for this is my only vehicles I have and need it to be running right for my kids. I have tried putting a ground wire from starter to frame and that never worked lol

I would start with pulling the driver (headlight) light bulbs and check for corrosion. While the bulb is out spray the socket with an electrical cleaner such as CRC. Might work, might not. May also be the socket wiring itself making intermittent contact.
Electrical gremlins can be tough to find. Good luck.

Lights that flicker are usually due to excessive AC ripple voltage coming from the alternator. Is easy to prove out. Disconnect the small wire harness going to the alternator. That will disable it. Then start the engine and see if the flickering lights still happen. You will most likely find that the issue is cleared up. Checking for AC voltage across the battery while the engine is revving slightly will also show up ripple voltage. Make sure your meter blocks DC in the AC mode so you don’t get fooled. There should be less than .1 volt of AC across the battery.

Some of the circuits and their fuses are powered even when the vehicle is turned off. That may be normal.

Suggest the basic battery alternator test first. You’ll need a DVM. Before first start of the day the battery should measure about 12.6 volts. Next, immediately after starting the engine 13.5-15.5 volts. What do you measure?