That's right I hate electrical. The only thing I hate about automotive other than cost. Well the electrical bug has hit my truck over the head so many times I can't see straight. I have replaced 2 starters in 2 1/2 year and 2 batteries. Not to mention the 3-4 times the gremlins desire to let it run after I work on it for hours. I finally say fine I'm done and it magically works. Now here is the situation as of today.
I installed a small sub and amp about 6 months ago. Did a bad ground and killed the battery charged it up and still won't start fix ground and after a few bourse of working the gremlins decide to let her run. Fast forward 2 weeks I park the truck having had zero issues. Middle of June my father in law starts the truck and runs it around town everything is fine. Middle of July bro in law try's to start truck not even a click battery is dead and won't charge. Today take battery in has a bad cell. Great buy new AC Delco Pro battery. Put in truck everything turns on and functions just fine. Except once again it won't even click no attempt to crank at all. Nothing, nada, zip. Well I check my grounds and wiring nothing. I am stumped.

 

Check the grounds at the back of the cylinder heads.

 

I need a little more info to help you. But just about truck like features line onstar. And what year truck is. Otherwise I'd say to do a draw test. And then I'd do a voltage drop test on the positive and negative battery cables. Both of these should help find the problem.

 

Wow sorry I just got back into town. Not 5 mins after I posted this my boss called and invited me on an all expenses paid Vegas trip. So it's a pretty basic electrical wise truck. No on star or power anything really. 4.8L 2000 gmc Sierra. I am going to do the voltage test in the morning. I will also check the grounds while I am at it.

 

I checked the cylinder head ground and it was tight and secure. I may pull the starter later today and have it tested again.

 

So I just checked the voltage on my brand new battery.
Before putting key into on position 12.4V
key on position 12.05V
Key back to off 12.21V
5mins later key in off position 12.27?!
Now I am getting zero movement from my starter no clicking or nothing. I am going to pull it now and run it down to oreilys and see what they say. Let me just say as this is my 5th time pulling this starter I hate pulling it. Thanks.

 

Well pulled the starter and got it tested. Everything looks good. I will re-install it tomorrow and do a voltage drop test and see if it is maybe a bad battery cable. I am starting to wonder if it could be a relay or just an ignition issue due to the remote start that was installed by someone else.

 

Did the drop voltage test and didn't find anything. I'm charging the battery just in case and will repeat the test after.

 

aftermarket remote start causing issues is where my money sits. i've seen quite a few issues come from that aftermarket trash.

what does the + terminal on the starter read with the key in the off position, and in the "start" position? put a volt meter on it and have someone try and start it and see if it drops, and how much. if nothing happens id be looking for a relay, ignition, or cooked wire between the igntion and starter.

 

Aftermarket remote start is where to look in to. There would have to be some kind of inline relay to enable the starting function on the vehicle without a crank signal from the ignition cylinder.