"Voltage Booster" for 31M AGM Battery

[rigtec]

nope it's doesn't work on my car since totally there is no alt s slot at all. tried replacing all my 7.5A fuse but no reaction totally to charge high and remain same 13.5-13.8 still. any soul able to do Magic to newer model 1 cable toyota denso alternator to let it charge high?

Hi BlueMica,

If you have a 5'th Gen 4Runner, then here's where to look: At the TOP of the "Engine-room fuse-box", you have the: SHORT-PIN, below that is the 10A RAD#1 fuse, below that is the, AM2 7.5A! Right next to that (to the Right), is the 20A H-LP HI (High-Beam fuse). And right below that is the: ALT-S 7.5A Alternator (S) (Sensor) fuse that you're looking for! :usa2:

Hope this helps!! ~rig~ :cheers:

 

[gmophree]

Are these voltage boosters required for 3rd Gen 4runners with "dumb" alternators?

I just ordered a 320A alternator and want to protect it and my AGM battery, any way I can.

 

[jawkdna]

Are these voltage boosters required for 3rd Gen 4runners with "dumb" alternators?

I just ordered a 320A alternator and want to protect it and my AGM battery, any way I can.

Might want to ask in the 3rd gen forum...

 

[Brian Wilson]

Voltage booster for AGM battery

I'm a big fan of AGM batteries Boat (4), lawn tractor, car (came with one) so I installed an AGM in my 2015 LTD and it went dead in a week.
Alternator was putting out 13.8 volts.
I bought the Voltage Booster Pro.
I'm an M.E.- Nice looking, well-made product, well done instructions with photos, easy install- 5 minutes.
It even has a nice (metal) selector switch if you want higher output (for colder weather or fully discharged battery)
Voltage is up to spec for AGM at 14.54V on the low setting.
I'll post again if I have problems, but it looks really good so far.

If your 4R is a daily driver you probably don't need an AGM. Their biggest benefits are extremely low self-discharge, quicker charging, can be oriented in any attitude-fully sealed, no outgassing.
When I lived in New England I used to park my lawn tractor for the winter, I used to run a charger to keep the battery up. Once I changed to AGM it could sit all winter (5 months) and easily start in spring with no charging needed.
I have no connection to producer of Voltage Pro- I just appreciate a well-engineered product. This post is entirely independent.

 

[jp.vegas]

I'm a big fan of AGM batteries Boat (4), lawn tractor, car (came with one) so I installed an AGM in my 2015 LTD and it went dead in a week.
Alternator was putting out 13.8 volts.
I bought the Voltage Booster Pro.
I'm an M.E.- Nice looking, well-made product, well done instructions with photos, easy install- 5 minutes.
It even has a nice (metal) selector switch if you want higher output (for colder weather or fully discharged battery)
Voltage is up to spec for AGM at 14.54V on the low setting.
I'll post again if I have problems, but it looks really good so far.

If your 4R is a daily driver you probably don't need an AGM. Their biggest benefits are extremely low self-discharge, quicker charging, can be oriented in any attitude-fully sealed, no outgassing.
When I lived in New England I used to park my lawn tractor for the winter, I used to run a charger to keep the battery up. Once I changed to AGM it could sit all winter (5 months) and easily start in spring with no charging needed.
I have no connection to producer of Voltage Pro- I just appreciate a well-engineered product. This post is entirely independent.

My OEM battery died a few months ago, I replaced with the X2 group 24 AGM and added the voltage booster pro at the same time. Definitely a well thought out and well made little board. I only drive my 4r once a week or so but whenever I start it, it cranks instantly, no slow whirring "I think I can do it" syndrome like it did lol.

 

[Chumly]

OK. I run an AGM Battery. I am in Florida where it is hot and my last AGM lasted about 4 1/2 years. The replacement was $165. (Costco again). I put on about 70,000 miles during this period. If I did get a Voltage Booster pro, is there any business case justified with my use scenario? How much longer would an AGM last in Florida if I made this change?

 

[fkheath]

OK. I run an AGM Battery. I am in Florida where it is hot and my last AGM lasted about 4 1/2 years. The replacement was $165. (Costco again). I put on about 70,000 miles during this period. If I did get a Voltage Booster pro, is there any business case justified with my use scenario? How much longer would an AGM last in Florida if I made this change?

Changing the charge voltage to a higher value for an AGM battery will not change the life expectancy. Depending on how you use your vehicle, it could be argued that it may slightly shorten the life expectancy.

 

[anarky321]

Hi Gill925,

The "Tell-tale lamp" circuit works this way... In the D/S (fuse) Junction-box, there's a 7.5 Gauge fuse HOT in on or Start!. It's directed through a diode, and an LED (Instrument Cluster//Tell-tale lamp circuit)! It goes to the Alternator L terminal #4 (Pink wire).

If the L Term at the alternator is generating voltage, then there's "NO GND" for the battery lamp to work, so it stays off. If there's NO Power/Voltage at the alternator's L Term, then the HOT Gauge fuse finds a GND at the L Terminal, and so it... lights-up to let you know the alternator isn't charging!

I would check that 7.5A Gauge fuse FIRST, before condemning the alternator! Also the IG Terminal #2 on the alternator, a 7.5A IG1 (IGN fuse); also in the D/S fuse-box, supplies power to the alternator's rotor, so be sure to check that fuse; W/O that power source, "NO CHARGING!"

Please let us know how you made out... although I see this is an OLD thread; but someone may STILL be able to benefit from these talent guys here who are helping out phenomenally; which is just why this is the LARGEST 4Runner forum in the U.S.A!

~rig~ Cheers!

hi, do you happen to know the wiring diagram for the 4th gen? i have no battery light at key on and no charging after 2 brand new alternators....continuity on 7.5a fuse and 140a fuse are both good...wire resistance good...do you know which wire i need to power probe out of the 3 at the alternator connector? i know 1 of them is the gauge wire and another is the exciter wire....not even sure what the 3rd wire is...very lost what else to check