got a strange voltage problem. i think

[black pearl]

we have not started the install yet so there is just factory replacement speakers in my Tahoe now (focal's) I have a optima red top in the stock location and did the big 3 upgrade, and everything was fine. I just installed a new xs power D3400 under the hood in the 2nd location. 1/0 gauge wire rand to the alt. and grounded to the alt bracket, now when I start the truck the voltage reads high 14's,(volts) after a few miles down the road it has dropped to mid to high 12's (volts) and this is with just a kenwood head unit and 2 set of focal components, NO AMP at all. any idea whats going on

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[09civic 5,000+ posts]

Your vehicle's ECU is regulating your voltage.

Ride around with your fog lights on.

 

[AL210]

Try disconnecting the 3400 and see if the voltage drop goes away. Was the 3400 fully charged?

 

[black pearl]

I don't have fog lights (its a LT lol) I may disconnect it tomorrow when I get back to work and see what happens

the 3400 was holding at around 11 volts out of the box from crutchfield

 

[matt_bennett05 10+ year member]

Your 3400 needs charging. If it doesn't help, you got a bad battery.

 

[black pearl]

Your 3400 needs charging. If it doesn't help, you got a bad battery.

ok thanks, this is my first go-round with AGM batteries and I don't own a AGM charger, will just driving around with it charge it or do I need to have it charged

 

[bgowdy 5,000+ posts]

ok thanks, this is my first go-round with AGM batteries and I don't own a AGM charger, will just driving around with it charge it or do I need to have it charged

you can use a regular charger just make sure you keep an eye on it at all times..... or got buy a smart charger

 

[black pearl]

what do I need to keep and eye on. from what I can tell from the sheet that came with the battery is not to charge it at more the 2.4 volts per cell, which is 14.4 volts right??? so don't most all battery chargers charge to 14.4 or do they put out more than that ?

 

[black pearl]

you can use a regular charger just make sure you keep an eye on it at all times..... or got buy a smart charger

ok I was able to find a smart charger here in town, when I went to leave the house, I disconnected the d3400 and checked the voltage and it was 12.3. this is throwing me for a loop

 

[Side Show 10+ year member]

sounds like a bad batt

 

[bgowdy 5,000+ posts]

ok I was able to find a smart charger here in town, when I went to leave the house, I disconnected the d3400 and checked the voltage and it was 12.3. this is throwing me for a loop

yea sounds like it may be bad. How long was it on charge? and are you going to get the smart charger if you already havnt?

 

[black pearl]

yea sounds like it may be bad. How long was it on charge? and are you going to get the smart charger if you already havnt?

when I said I disconnected it, I meant I disconnected it from the alternator so it would not be hooked up anymore. then I check the voltage and it was in the mid 12's. I haven't put it on charge yet, I was going to do it tomorrow at work

 

[bgowdy 5,000+ posts]

when I said I disconnected it, I meant I disconnected it from the alternator so it would not be hooked up anymore. then I check the voltage and it was in the mid 12's. I haven't put it on charge yet, I was going to do it tomorrow at work

oh ok. even tho it was on the alt it still probly needs some charging. just put them on like a 2amp charge on a smart charger and leave it on there for a while, may take a few hrs

 

[black pearl]

oh ok. even tho it was on the alt it still probly needs some charging. just put them on like a 2amp charge on a smart charger and leave it on there for a while, may take a few hrs

thanks for the help man.

 

[bgowdy 5,000+ posts]

thanks for the help man.

np....