random voltage drop

[Incredibad]

i have a 2015 silverado 1500 stock alt kicks out 150 amps i have a rockville class d mono amp that that should pull 155 amps at 1 ohm my subs are atm 1.5 ohms so i should be ok i have taken my truck to advanced auto and had them run the diagnostic on my charging system i didnt feel it was a great test but every thing check out ok. i am able to monitor my system voltage through my head unit i have seen my system drop to 12.4 on the drive home which i know is not good any ideas to try and fix it budget is a bit tight and i dont wana just start swapping things.

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[Slo_Ride 5,000+ posts]

Random voltage drops are usually caused by not so random bad connections.

 

[Incredibad]

thank you i will try and look over all the connections tomorrow

 

[n2audio 5,000+ posts]

How long does it stay at 12.4v?
If your radiator fans are kicking on simultaneously you could be getting a ~30A hit which would momentarily drop any electrical system to battery voltage. As long as it's recovering in a few seconds - it's doing what it's supposed to do.

 

[Incredibad]

well i have about a 20-30 min ride home it was at 12.4v half the way and i even let the truck stay running for anoth 5 to 10 mins when i get home it stayed at 12.4 the whole time

 

[n2audio 5,000+ posts]

12.4v is about what a healthy battery will do when the alternator is dead -- or not doing anything.
How many miles on the truck? Always a lot of amplifier power? Do you blast it a lot or not very often?

Alternators don't always just die all at once. I had an alt once that died on the car and left me stranded, and then test fine when I took it out.

 

[dragon.breath 10+ year member]

You don’t have a problem. Your truck has the “regulated voltage control” (RVC) system. The computer turns the alternator on and off to increase the fuel mileage. If the computer senses a increased load, it will turn the alternator back on.