"Voltage Booster" for 31M AGM Battery

i told him

it's not backwards for the vehicles that it fits in the other way, that's why the feedback is positive, but on our vehicles it can only fit in one direction which is backwards for the diode. if you were physically able to turn it the other way it would work. i wanted to do a side by side comparison to see which gave a better voltage boost, if i can cut the epoxy off i'll flip the diode and compare when the HKB arrives

I sent the seller on ebay a message asking if he'd make one with the proper orientation/polarity for the 5th gen. He did and it was on my door three days later. Excellent service. Works as expected. No complaints.
 
Confirmed the eBay seller toyo22r is a great guy. He quickly made the proper polarity adapter for my 2013 and got it my way in less than a week. Plug and play.

I didn't see where this was confirmed - but the engine bay's fuse box cover STILL FITS with this installed (unlike if you use an "Add a fuse" adapter in the interior fuse panel as I did for my radar).

I will absolutely recommend you carry the replacement 7.5amp low-profile micro fuse (?) in case you need to remove this for whatever reason. The adapter uses a mini fuse (short protruding legs). I keep an assortment of each in my glovebox...

Toodles! :music:
 
ERjjPial.jpg


YmSI1k6l.jpg

Decided to toss my ebay booster with one that has some improvements.

This one allows you to retain the fuse. Switch between stock voltage and boosted voltage (perhaps in the case your AGM batt fails and you get a temporary one from the tow truck). Uses a higher current rated diode.

So far this is performing 100% identical to the diode solution and I'm extremly happy with it.
 
ERjjPial.jpg


YmSI1k6l.jpg

Decided to toss my ebay booster with one that has some improvements.

This one allows you to retain the fuse. Switch between stock voltage and boosted voltage (perhaps in the case your AGM batt fails and you get a temporary one from the tow truck). Uses a higher current rated diode.

So far this is performing 100% identical to the diode solution and I'm extremly happy with it.

damn the stuff you think up, is amazing! looking forward to buying one too!
 
Decided to toss my ebay booster with one that has some improvements.

This one allows you to retain the fuse. Switch between stock voltage and boosted voltage (perhaps in the case your AGM batt fails and you get a temporary one from the tow truck). Uses a higher current rated diode.

So far this is performing 100% identical to the diode solution and I'm extremly happy with it.

does the cover still fit on with the switch?

also, link?
 
Decided to toss my ebay booster with one that has some improvements.

If you are going to sell that, you might as well put a polarity revers switch or jumpers on it for people that need the diode reversed.

Or terminal block for diode so they can reverse that and/or replace the diode should it ever go bad. In fact you also put a holder on it to carry a spare diode.

.... and if you want to cover absolutely all the bases, put a fuse holder on it too. that way the whole deal can be pulled and a simple original fuse be replaced.

I can't imagine what anyone could ever want beyond that.

You would get...
OEM - spare fuse
Switchable
Diode Polarity reverse
On/Off
field replaceable diode and spare diode

It would all fit on that same board.

ETA: You could also eliminate that switch with terminal blocks. It's a point of mechanical failure for a device that may never be used. Jumpers with crimped ends in screw blocks would be nearly as easy to use.
 
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does the cover still fit on with the switch?

also, link?

Cover fits. Don't have a link but you can PM me if interested.


If you are going to sell that, you might as well put a polarity revers switch or jumpers on it for people that need the diode reversed.

Or terminal block for diode so they can reverse that and/or replace the diode should it ever go bad. In fact you also put a holder on it to carry a spare diode.

.... and if you want to cover absolutely all the bases, put a fuse holder on it too. that way the whole deal can be pulled and a simple original fuse be replaced.

I can't imagine what anyone could ever want beyond that.

You would get...
OEM - spare fuse
Switchable
Diode Polarity reverse
On/Off
field replaceable diode and spare diode

It would all fit on that same board.

ETA: You could also eliminate that switch with terminal blocks. It's a point of mechanical failure for a device that may never be used. Jumpers with crimped ends in screw blocks would be nearly as easy to use.

Eeek! That's a lot. I actually built the board to fit both 4runners and FJ (you'll see the through holes and traces that are unused) so this is the max size of the board. Also the traces are built to handle 10amps so the spare parts will not fit. I also don't like jumpers as those can go missing (imagine losing it in the engine bay or orient the jumper the wrong way)

Anywho, electronics fail which is why I built this (wanted something with a bit more quality) however I'm willing to bet I'll lose my AGM battery before this booster fails so flicking a switch to go non-boosted while getting my battery warrantied/replaced was ideal for me and probably 99% of us.

zXtjG75l.jpg


Also got a pic of the booster in action :)
 
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The eBay one also retains the fuse, but agree the 1Amp diode is questionable. My eBay version is holding up just fine. If it dies, simply remove and replace with the stock fuse...

Nice package in any regard!!! (lol - I said "nice package" :cheer2: )
 
My HKB fuse has been doing great. Seeing a solid 14.2v. Only issue is the voltage is getting a little high on cold start on cold days. Seeing up to 14.8 volts. Not a problem for my odyssey batteries but I'm wondering about the vehicles electrical system?
 
[MENTION=153545]LOLSNOW[/MENTION] how hard would it be to make something that is adjustable? Or have 2 diodes and a switch for low/high?


Here is my issue, and it's something that anyone who has a 31m in very cold temps should be aware of:

The required voltage to properly charge your batter varies with temperature. For my battery is is 18mV per every 1.8 degree from 77 degrees, you subtract for temps above and add for temps below 77 degrees.

I just noticed that my resting voltage on my battery was getting kind of low, which surprised me because in the current temps we have my fridge really only runs if i'm driving long enough to heat up the cabin enough for it to kick on a little, and regardless my daily driving is usually plenty to recharge the battery even it was. i was really confused and worried that something was wrong until i remembered that temps effect the charging voltage and looked up the spec for my battery.

This morning it was 10-15 degrees here, which means that that charging voltage needs to be about .6V higher than normal. My battery normally requires 13.8V-14.6V for charging, so factoring for the low temps and I really need at least 14.4V. With the HKB booster I'm running about 14.3 (it varies between 13.9-14.4ish), that that means is that in these low temps I'm barely charging my battery!

If you have a 31m battery in low temps make sure you check your charging specs and keep an eye on your SOC, you may need supplemental charging if it's cold enough
 
I finally got all the parts to make a booster. Yesterday I did a test fit. It has gotten very cold here. I'm still just using the standard battery.

My truck has run at 13.2-3 since this Spring when I bought it. I stopped loking at the voltage.

So now as I'm testing I notice my voltage has jumped up to 13.6-9 range... no booster.

The booster of course adds 0.2-3 volts although I didn't leave it in long. It was just a test fit. I need to solder it.

I was wondering if my battery was doing something different, if the truck knew it was cold and doing something different, or what the heck is going on.

So I put a CEK on the battery and it's fully charged but my running voltage is anywhere from .3 to .6 volts more than it used to be.

If anyone knows why that is I would be interested.

====
[MENTION=113833]e60ral[/MENTION] what you want would be very easy to do. You just need a switch that selects 1, 2 or however many diodes you want. Each diode is good for .2-3 volts.

The easiest way would be to use 3 diodes.

The switch would select

This -----|-- .2-3 drop(increase) one diode
Or
This ----|----|--- .4-6 drop(increase) two diodes end to end

The diodes don't cost anything.

A switch that is On ON ON would do just fine.

Position 1 gives you one diode - .3 drop
Position 2 gives you two diodes - .6 drop
Position 3 gives you no diodes - normal setup no drop

You need a SP3T - Single Pole Three Throw switch. The single pole is your fuse connection. The three throws are Pos1,2,3 that lead to Sense wire on alt.

You can find them rotary or toggle.
 
Love this forum guys and this is my first real post... Any update from someone that has ran a “boosting fuse” for awhile? Any downside? I’m installing a dual battery kit in my 2017 TRD off roadand already have a group 35 agm so that is going on the passenegr side. I am debating about adding a group 24 agm in the original position but sounds like I would need more voltage (boosting fuse). The other option is to keep the OEM battery and install a ctek ds250 dc to dc charger and run it to the agm secondary battery to boost that voltage. Would also like to install a Blue Sea ACR so maybe “boosting fuse” is the way to go and run two agm’s. Any thoughts? Thanks
 
Love this forum guys and this is my first real post... Any update from someone that has ran a “boosting fuse” for awhile? Any downside? I’m installing a dual battery kit in my 2017 TRD off roadand already have a group 35 agm so that is going on the passenegr side. I am debating about adding a group 24 agm in the original position but sounds like I would need more voltage (boosting fuse). The other option is to keep the OEM battery and install a ctek ds250 dc to dc charger and run it to the agm secondary battery to boost that voltage. Would also like to install a Blue Sea ACR so maybe “boosting fuse” is the way to go and run two agm’s. Any thoughts? Thanks
No issues with mine, I do still need to plug in and top off on occasion if I'm not driving enough during the week to fully recharge the battery, and also in extreme cold when I need a higher voltage than even the booster can provide.

Sent from my SM-G930V using Tapatalk
 
Love this forum guys and this is my first real post... Any update from someone that has ran a “boosting fuse” for awhile? Any downside? I’m installing a dual battery kit in my 2017 TRD off roadand already have a group 35 agm so that is going on the passenegr side. I am debating about adding a group 24 agm in the original position but sounds like I would need more voltage (boosting fuse). The other option is to keep the OEM battery and install a ctek ds250 dc to dc charger and run it to the agm secondary battery to boost that voltage. Would also like to install a Blue Sea ACR so maybe “boosting fuse” is the way to go and run two agm’s. Any thoughts? Thanks

I've been running the hkb fuse in my tundra (odessy agm) and Tacoma (northstar agm), both with stock alternators for about 4 months. No problems. On my 4runner I switched to a DC power alternator running at 14.2 Volts (northstar agm). Also been great. All vehicles are single battery though.
 
Love this forum guys and this is my first real post... Any update from someone that has ran a “boosting fuse” for awhile? Any downside? I’m installing a dual battery kit in my 2017 TRD off roadand already have a group 35 agm so that is going on the passenegr side. I am debating about adding a group 24 agm in the original position but sounds like I would need more voltage (boosting fuse). The other option is to keep the OEM battery and install a ctek ds250 dc to dc charger and run it to the agm secondary battery to boost that voltage. Would also like to install a Blue Sea ACR so maybe “boosting fuse” is the way to go and run two agm’s. Any thoughts? Thanks

I bought a Projecta DC/DC/Solar.

My reasons were...
1. Standard battery is cheap, works for many years, and runs the way the car was designed.

2. Projecta provides the correct voltage for whatever Aux Batt. I install.

3. Solar ready

so Standard + AGM + Solar and the truck is operating as designed. The Aux is being cared for with modern tech. It just made sense to me. I'm not concerned about being able to press a switch and jump start my main batt. So I have much smaller gauge wire connecting everything.

I made a diode booster and it failed. I'm sure that was just a fluke. It should not have failed. No one else is reporting failed diodes. I was just running it on the main batt. though, just to check voltages. I still wasn't seeing numbers that would be ideal.

It's really a $$ thing. You are talking hundreds vs $10.

That's just how I feel about it. Many ways to make it work.
 
Thanks! Will look at the Projecta dc to dc charger. I was told the ctek one is now discontinued and I just got word so need to track another one down.
 
I too am interested in the Projecta DC to DC charger. How do you like it so far and how did you set it up? Are you running a solar panel on it?
 

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