Can anyone help me with a Charging Issue I have been having on my 2008 Hummer H2 SUV, 6.2 L Engine. It started having issues with Discharging as I was driving or sitting still as well. Anytime I shut the Engine Off and Re-Started it, it would Begin to Charge again, but this would never last. I Checked All Of the Connections, and Had already put a New Battery in. I Replaced the Alternator assuming this was the Issue, but My First Drive I thought it was okay, and after I made a stop I found that it was discharging again on the way back. I had to Shift to Nuetral so I could Turn it off, Restart the Engine and it was good again after a few Repeats to get home. I'm an Electrician by trade and have no problem with Auto Wiring as well and my Code Reader Doesn't Read Any Codes Even When it Discharges Enough that the Battery Alarm Lights Up on the Dash and the Meter is Severely Discharged.
Appreciate Any Help From Anyone,
TonyH

 

My 08 is doing the same thing but I haven't had time to work on it until now, been working every day for the last 3 months.

The 08 has a current sensor that measures the current being pulled form the battery and adjusts the charging system to maintain the needed level. There are a lot of other systems that are monitored by the BCM to maintain the charging system. You'll need a dealer level scanner to really get into the BCM and look at what's going on.

I have them and will try and get into it in the next couple days, once I get it figured out I'll update this thread, It may not be the same issue that your seeing but it does sound similar.

Mine is setting a DTC so I'll start looking there

Neal

 

Check the RVC fuse.

 

Mine doesn't discharge, but it'll go down to around 12.8 or so. It just goes up and down when it wants. I thought I read somewhere that if you push the tow button it will give you more charging. Lol, I'm sure it read a little different in the book. It's never left me stranded so I don't even worry about it anymore. I can read trouble codes and check engine (OBD) codes on my radio screen, also reset them too. It's came in handy sometimes. Discharging means like 11.5 volts (Example)?

 

Thanks For The Information Everyone, I am going to check the RVC Fuse right now, but I was Curious as to how you are able to "Read the OBD and Trouble Codes on the Radio Screen ? This would be good to know if there is any future issues. Thanks in advance !

 

10.1 inch. Lol, go big or go home. I absolutely love this thing. I got the one w/o built in Navigation. It will mirror my phone and show Google maps on it also.

 

WTF? I wouldn't do it without a built in look! Btw, what's up with the psi's?

 

Lol, they're stupid. I need to change all 4 of them. I like the pressure on the high side. They all check out the same with a guage.

 

was able to pull the code from the PCM today, P0622

While watching the live data stream the GEN F terminal drops to 0 while idling, GEN L is also doing some odd stuff

Didn't have time to do any trouble shooting today but will in the near future

Neal

 

P0622 – Alternator, field control -circuit malfunction