Can you check what voltage your alternator is putting to the battery?

[chayos00]

Hey guys, I'm upgrading my amp for my subs as the 14 year old amp finally died. However I checked my voltage at the battery terminals when the truck was running at idle and it was only putting out 13.4v. I checked this against my wife's car and it's @ 14v. My battery is less than 1 year old, it's a Duralast Gold top 24F-DLG. I have not checked the battery voltage is by itself yet.

Can you guys verify what your voltage is with your vehicle running to tell me what you guys are getting, I'm wondering if my voltage regulator is going out or if this is a normal voltage for a 4Runner.

 

[Brutalguyracing]

seems about right

 

[txclimber]

I agree that's about right. It may vary depending upon the load and RPM's. But anything above about 13.2 is plenty.

 

[chayos00]

I agree that's about right. It may vary depending upon the load and RPM's. But anything above about 13.2 is plenty.

I tested this with the truck in idle, with very little load on the electrical system. Granted 13.2 is good for keeping the battery charged, but I was just curious as the higher voltage that the system puts out the better it is for the amplifier, so I was just curious what others were getting as my wife's car tested higher in voltage.

 

[HiLife]

I haven't done the big 3 on mines yet and my volts are at 13.8-14.2. I read on the past thread here that some members doing the big 3 reported on a boost of alternator voltage to 14.3.

 

[chayos00]

I haven't done the big 3 on mines yet and my volts are at 13.8-14.2. I read on the past thread here that some members doing the big 3 reported on a boost of alternator voltage to 14.3.

I plan on doing the big 3, once I can figure out a good decent brand of wire, that doesn't cost an arm and a leg. I'm hoping to find true OFC wire (copper) and not CCA, but we'll see what I can find. If the big 3 upgrade gets some higher voltages like a big boost, then Toyota didn't do something right from the get go!

Also, is this on your 2000?

 

[HiLife]

Yes the voltages is on my 2000. I was going to do the big 3, but a trip to the alignment shop yesterday changed my priority to suspension parts.

NAPA, or most reputable auto electric shops will have great wires.

 

[Brutalguyracing]

Wtf is a big 3

 

[LTDSC]

Wtf is a big 3

http://www.stevemeadedesigns.com/board/topic/13280-how-to-do-the-big-3-tutorial/

quite popular on GM forums. Ive never done it however.

 

[BlackWorksInc]

Wtf is a big 3

Basically putting larger battery, alternator, and starter cables than factory. Its not that the factory cables are inadequate or bad (at least typically, some vehicles are just designed poorly/cheaply); but rather they are the result of compromise between factors such as: weight, quality, cost, ect. So some owners put larger diameter cables which create less resistance and provide even better current flow in the system.

As for the OP's question, typically at idle around 13.4v is pretty normal; if you turned all the loads on (i.e. high beams, blower motor on High, A/C On, Radio On, dome lights on, ect) and revved the engine to about 2500RPM you'd probably see it jump a little past 14v as the alternator will scale up current/voltage based on vehicle load (it also produces better voltage/amperage at "peak" RPM typically around 2500RPM and above due to the way generators work.)