Did you do the alternator replacement yourself? You should not need to purchase an AC Delco, as long as the remanufactured is compatible. I assume the control wiring connectors were the same and it had the same amperage output as the factory. Was it the same type of battery and capacity. Some charging system require the new battery to be registered, so the system knows it is new.

Why did you run another ground wire. The charging circuit is typically grounded to the engine as well. If you are handy with a multimeter, voltage drop measurements are easy. You should have less than 250mv total for the positive and negative side. Make sure all battery and cable connections are clean and tight.

These system are smart charging systems and there are multiple factors and inputs that goes into the system to determine the charge mode. The current sensor is one of them and it should be on the ground side and is direction specific. If the sensor is reversed in direction, say when the ground cable is replaced, it will not correctly read current in and out of the battery.

You can force the system into bulk charge mode by turning on the heating and fan system on full and turning your lights and windshield wipers on. When it is fully charged and very low loads on the alternator, it can drop down to 12.6 volts.

What type of battery voltages are you seeing at idle and in drive, with no loads and full loads?

 

How do y8u

Did you do the alternator replacement yourself? You should not need to purchase an AC Delco, as long as the remanufactured is compatible. I assume the control wiring connectors were the same and it had the same amperage output as the factory. Was it the same type of battery and capacity. Some charging system require the new battery to be registered, so the system knows it is new.

Why did you run another ground wire. The charging circuit is typically grounded to the engine as well. If you are handy with a multimeter, voltage drop measurements are easy. You should have less than 250mv total for the positive and negative side. Make sure all battery and cable connections are clean and tight.

These system are smart charging systems and there are multiple factors and inputs that goes into the system to determine the charge mode. The current sensor is one of them and it should be on the ground side and is direction specific. If the sensor is reversed in direction, say when the ground cable is replaced, it will not correctly read current in and out of the battery.

You can force the system into bulk charge mode by turning on the heating and fan system on full and turning your lights and windshield wipers on. When it is fully charged and very low loads on the alternator, it can drop down to 12.6 volts.

What type of battery voltages are you seeing at idle and in drive, with no loads and full loads?

How do you register a battery?

 

There is a lot they, the dealership or independant can do without seeing a trouble code. They can go in and monitor actual charge voltage, current and duty cycle. Their tool can command the alternator to output full charge or any amount below that to test that both the alternator is able to be controlled by the engine computer and that the alternator is responding correctly. they can perform voltage drops. You can disconnect the control wiring on the altenator. This will force the alternator to use the internal regulator, and keep the voltage at a constant 13.8v. You will get a message on your dash or CEL, but at least it will not leave you stranded until you can find someone that can fix it.

 

well I went to a crappy dealership then because they didn’t hook it up at all and said there were no hard codes to run. They said if I was close by and it happen again to bring it back in so they could scan it.

the alternator was replaced by my mechanic and fiancé. A trusted mechanic because I don’t trust dealerships unfortunately.

my mechanic decided to run the extra ground wire because he wasn’t sure if that was the problem.
I’m not 100% sure on the readings they are getting when testing it - I’ve just been told they are in good working order and where they should be.

If my battery current sensor was on wrong wouldn’t it show the code all the time versus just randomly like it does?
Usually when it does this it will enter battery save mode and shut everything off on me. im assuming the alternator is compatible as it is the one my mechanic ordered and put in my vehicle.

 

I really wish when people posted a problem, once they figured it out and got it fixed that they posted what the problem was...

 

Vehicle modules do not set a code for all situations. Codes are set when conditions are significantly outside the norm. If the current sensor was on backwards it would report the incorrect charging current or loads. When electrical demands increased, it would see it as charging current rather than a load and not increase current when it should.

Conducting a voltage drop problem on a battery cable or ground cable only take a few moments. Sounds like your mechanic is just guessing, and not verifying what is actually wrong.

Have your fiance remove the control connector on the alternator and then check the voltage. Better yet, have him join the forum.

 

I had this same issue when we replaced the alternator in our Traverse when we tore it down for the timing chains. I used a CarQuest brand from Advance Auto. It was about a year before the service charging system light would come on. First I replaced the battery, then the current sensor. Ruling those out, I went to Advanced and bought another alternator of the same so that I could warranty it. Had my mechanic install the new one and the light was still there. To make a long story short, we ended up replacing the ECM at the dealer after I laughed at their claim of GM support suggesting to use a Delco alternator. ECM replaced, still had the issue. I am still convinced my Traverse is cursed. AKA the cursed Traverse as I refer to it... I called a few Chevy dealers around the country and asked their thoughts. All had told me stories of aftermarket alternators that had caused that problem for their customers. The fix was a Delco alternator. I'm not sure if maybe it's just the brand of alternator, but the Delco works. I found mine online for about $320.

 

I actually knew a mechanic who had done countless alternator swaps with aftermarket brands. He said that he had learned that some GM vehicles, for whatever reason, will not seem to like a non-Delco brand alternator. He had a couple instances where a Delco alternator made it go away.

When I replaced mine this summer, I did not take a chance and got an AC-Delco with low miles from a salvage.