2015 GMC "smart" charging system

[ToNasty]

I told you the way to "trick " the alt. Turn on tour lights.

All of the info I gave you matters.

I figured you didn't want dual alts so I said to turn the lights on

I'm sorry if you are angry but I wasn't trying to be a dick

[Seni]

I'm not angry im frustrated.

Lights on does not make the system charge

light i said ive had every load in the truck lights AC blower etc etc etc and it will not charge to 14.5v like you say you're truck does.

you are correct i dont want to go to 2 alts if i dont need to.

but now i will have to track down the sensor to BCM wire and figure out a resistor to trick the BCM into thinking the system voltage is to low so it tells the alt to charge.

which is a few hours of screwing around and may not work without messing up other systems and throwing warning lights. but its worth a try.

Thanks for your help anyway.

[ToNasty]

It's on the oem ground cable

[Seni]

Ya. but then it's measured by the sensor and sent to the BCM which converts it to either a ref voltage or 12v to the ECU which then controls the alt. and theres problably at at least 2 circuits in the way.

[MotorCityFats13]

my friend has a 2015 impala and it reads 13.8 - 14.2 no matter what we do with it.... I guess it does not have this charging system setup

[MotorCityFats13]

funny how somebody has not made a workaround for this if its been around since 05

[Seni]

i'm pretty sure thats what my truck did before i installed the optima. i never remember seeing it go anywhere but almost straight up at 14v.

now it basically shuts off or charges just enough to maintain the battery

[BassJunkie]

Ya. but then it's measured by the sensor and sent to the BCM which converts it to either a ref voltage or 12v to the ECU which then controls the alt. and theres problably at at least 2 circuits in the way.

Well you appear to know more than anyone here, not sure why you made this post. Good luck.

[Seni]

I was hoping someone already had a workaround for it. the fact that there isn't one is a sign that it can't be fooled into charging without cause other problems.