My battery light came on, and my battery was weak. I replaced the battery first, as it was actually bad after testing. Ran it around town for a few errands, and then tried to crank, battery dead once again? Tested alternator, no charging, so I go get a new Delco alternator and installed it. Drove a few errands, and it still cranked when I got home and the battery light was out, so all seemed to be resolved. Got in this morning and drove less than 2 miles and battery light was on again, so went home and turned off the ignition and tried to crank, battery dead once again.

I then jumped it off and tested the alternator and it was putting out only milliamps at the battery. Tested the alternator at the battery connection at the alternator, nothing but milliamps? Is it possible I got a bad alternator off the shelf at AutoZone, or is something killing my alternator? So frustrating and I'm at my wits end with this thing. It wasn't terribly difficult to change out the alternator, but the idea of having to change it again is frustrating.

Any thoughts or suggestions? Is something killing my alternators, or do you think the new alternator is bad off the shelf?

 

The parts houses can test the alternator and tell you if its good or bad and what has failed if anything.
The charging system on your truck is tied into a few modules so it can keep the battery in good condition,
there is a current sensor on the negative battery cable just down from the battery that sends a signal to the BCM which interns assists with charging

I would pull the alternator and have it tested,

Neal

 

Intermittent charging can all be caused by bad connections from the battery cables. Have you checked the cables at both ends for clean and tightness.

 

Thanks for the suggestions. I will look into these issues and respond with a fix if I find one.

 

Yeah, I was watching Scotty on you tube and he mentioned that. That's why you should never connect the Neg jumper cable directly to the neg post on the battery. It tells the computer your battery is fully charged. So when your Battery is low the computer will think it's full and won't charge correctly. Always connect to the Engine Block. My 09 H2 has a spot on the alternator bracket marked " Ground" used for Jump Starting.

Gone are the days of internal Voltage regulators. It's now compute control ...My GOD....What Have we Done.

 

OK, I tested everything I could think of and every fuse, no matter what it went to, and found nothing amiss, so I removed the "brand new" alternator and returned it for a replacement. I noticed immediately upon receiving the new alternator that the box was different, and when I took the new alternator out, it had tags on it and some instructions in the box, none of which the previous "new" alternator had. I went home and installed it and viola; it is now charging the battery and my battery light has gone out on my dash.

I think the previous alternator they gave me at AutoZone was a bad one returned by a customer that got mixed up with the good ones. It looked fine, but it did not charge and the new one works flawlessly so far.

I do have a new problem now though. I will do some searches here and see if there is a post on it, but now that I have full power restored, my radio is working fine, but the screen on it is black. At first, I thought I had no radio at all and assumed I blown a fuse, but the fuse is fine. The radio works and plays music just fine, I just can't see anything on the screen. No radio screen, no navigation, no maps, no nothing. Just a black screen. Any suggestions?

 

Oh ..No...!!!!
Guess what..I had the same problem after changing a battery out. It was done at Advance auto parts. They hooked a Battery charger to my Battery leads and changed out the battery. A little while later the screen went black like yours. Then after some off /on starts it would come back. Then go out again. The radio worked fine except like yours ... a Black screen. I sent it out to Infotainment for a repair. They said it ran fine on there bench. They charged me $80.00 bench fee. I installed it and same thing off and on screen.

The other thing I notice is that the NAV unit was off by at least a 100 feet, Check your nav it the screen does come back.

I still have it in the box it works. I bet if I hook it up now if would light the screen and play. That radio is for 08 and 09 Hummers. (4 Channel which runs two amps.

Anyway ..Next time I change the battery I'm pulling the 30 amp radio fuse as the radio is always powered.

I ended up buying a New Radio and having it programmed at the dealer as it is only 08 and 09.
Good luck maybe it will come back and stay on. My thoughts are anytime you do anything with the electrical ...pull the radio fuse.

 

I would disconnect the battery, let it sit, and reconnect and restart to check if the LCD comes back on. IF it is fried, you can get a replacement nav on eBay programmed to your VIN at a reasonable price - just make sure the nav unit is the same part number (the part nbr is on a sticker on the top of the nav unit) and supports your specs (bose/non-bose, rear camera/no camera). Several eBay sellers will fully program one for you... plug and play.

 

Thanks for the tips, guys. I will try disconnecting and reconnecting the battery and see what happens. I wouldn't mind upgrading the radio to something more current anyway, so if fried, I may just replace it if that is not too difficult to do. I will look into it. Anyone else swapped out their radio themselves? If so, was it difficult and do you have any tips or recommendations on that endeavor?

 

There is procedure for removing the metal surround. I started at the bottom left and up the left side around the top and down to the bottom. Depending on the conditions it will either snap off easy or fight you. When I replace anything with those clips that are on there I use a Non Petroleum grease so they come off easier next time.

The Dash Vents are part of the assembly. After you get the surround off you will see how the radio is mounted and should pull out nicely. Bring it out slow as the GPS antenna Lead is very thin on the left side on my 09. Just remove it slowly and disconnect the connectors.

Also there are 3 rectangular plugs on the rear.. Plus the FM antenna plug...And the GPS antenna connection. Use care and look at it carefully. The way that disconnects is funky. Don't over stress that GPS plug ,as it can be damaged.

If some one has a pic of the Faceplate showing the locations of the clips and the removal instructions ..maybe you could post that here...HUMMERZ...LMAO