Service Battery Charging System

[RAWVORTEC]

2007 suburban LTZ. I had this warning come up a 2 weeks ago, and I had both alternator and battery tested. Alternator was good. I needed a new battery. It's been hot and I've been pumping ac ever since and it's been running great. I had the warning come back today under normal driving. I hadn't been sitting or romping on it. What has been the cause of this for anyone else? I can see some 10+year old discussions about this, but I wanted some fresh minds to educate me.

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[Doubeleive]

clean your charging cable connection, and both positive/negative wires, master fuse connections. if the problem persist's you may need to get new battery cables, presuming battery and alternator still check out good, there is the possibility the alternator is failing or maybe it's just getting to hot in the summer heat. It has been noted that the battery cables on these trucks can corrode on the inside, replacing them has solved a variety of power problems for some people.

 

[RAWVORTEC]

10-4 I'll check those out

 

[RAWVORTEC]

First picture is without ac running while driving, second is with ac on. Before yesterday it was sitting at 14 all the time. I checked all connections and they looked good.

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[Doubeleive]

I don't know, you might want to have the alternator tested then, I have been going thru circles on similar issues myself with low charging, I finally ordered a mechman but it's still going to be 3-4 weeks before it even ships, I haven't been getting a service charging system but have been getting around 11v (sometimes) which I don't like it puts a drain on the battery, the mechman is supposed to give me 180+ amps at idle (240 amps max), the stock alternator is 160 amps (max), these trucks have a RVC regulated voltage control which supposedly creates better fuel economy which I think is a crock, it can't be much, mine will stay in fuel economy mode even at 11v which it shouldn't but the dealer said it's normal. I have the big 3 upgrade and new ground cable with the sensor and the whole bit, everything is clean and rust free, makes no sense......

 

[donjetman]

2007 suburban LTZ. I had this warning come up a 2 weeks ago, and I had both alternator and battery tested. Alternator was good. I needed a new battery. It's been hot and I've been pumping ac ever since and it's been running great. I had the warning come back today under normal driving. I hadn't been sitting or romping on it. What has been the cause of this for anyone else? I can see some 10+year old discussions about this, but I wanted some fresh minds to educate me.

Mine has something called "Regulated Voltage Control"(RVC). Maybe if you unplug it? Here's a thread about the device:
https://www.tahoeyukonforum.com/threads/figured-out-how-to-keep-steady-voltage.59534/