AGM BATTERY CHARGING - ALTERNATOR VOLTAGE BOOSTER

https://www.tomorrowstechnician.com/toyota-charging-system-diagnostics/

 

OK so i went ahead and did this. After driving, charge voltage at idle was 13.8V. After mod and idling for a little bit, charge voltage was 14.5V. I wasn't able to find an empty slot in the fuse box to put the fused add a circuit in. so i put it in the ECU-B slot, then added the 7.5A ECU-B fuse to the bottom of the add-a-fuse. thanks for the inspiration, great idea!!!

 

WOOOHOOOOO!!!! I knew it would work. I’ve had my truck apart for awhile. I plugged it in and it looked just like the pic I drew, but I haven’t been able to start it. I just got my truck mostly back together today. Tomorrow it will be the test drive. Thanks for confirming that my idea works.

 

yeah i had to convince myself with a bunch of resistance checks to make sure it really was a series connection and there werent any leakage paths. this was the first i had heard of an add-a-fuse.

 

I got my truck back together. Yep, it works. I ground the tips off the diode a little bit so that it fits into the low profile mini add a fuse a little better.

 

I experienced a subtle, intermittent, high pitched whine from the area of the alternator, a few weeks after installing the Australian diode. Took out the doide and whine went away. Haven't put it back.

 

This was my concern, overworking the alt. If it’s causing it to whine, it can’t be good.

 

It was only obvious at idle. If it was whining and I tapped the gas even slightly it would stop, sometimes it would come back. I live in an area that eats batteries and the typical life span is only a couple years anyways. I can get home easier on a dead battery than an alternator. Just means I keep the truck plugged into a battery charger during its downtime.

 

I used to work at a repair shop that refurb alternators. Most (not all) of them are designed to output out as much as 16volts. If not more or lessdepending on the brand and type and design.

With that said if your alternator is starting to whine. It might be time to change it out

 

yep 15 volts is no problem. The rvc alternators put out up to 15.5 volts from the factory, I’m sure the rotor and stator are made by the same company that make ours, or of very similar construction. If it’s wining, it’s because it’s time to refurb the bearings and maybe brush assembly.

 

Anyone have a HKB Adjustable voltage booster laying around to sell ?

 

The truck only has 55k miles on it, so it needing a rebuild already, is hard to swallow. Though anything is possible and could fail early.

 

Has anyone had an issue with a relay being stuck ON after this? I haven't verified yet that I have a bad relay yet. But this morning I went to shut off my headlights and they stayed on, granted I have a retrofit with a Morimoto Moto-Control harness but that shouldn't be causing the issue as its simply doing what the input tells it to (i.e. the headlight relay). I haven't had any issues with the Moto-Control harnesses in previous installs, though anything can happen. I will be looking into it after work to verify whether it is a bad relay or not, but I believe it might be.

 

12 volt relays are rated from 9-15 volts. I can't see how this would be an issue caused by voltage. More than likely the relay, which is a mechanical part, is stuck.

 

Not to mention there also made to handle high amps

 

Thats what I was thinking too. I'll have to diagnose more when I get home tonight. I've only had the retrofit for a few weeks with all new parts and parts I have used in the past. Chances are the Moto-Control harness went tits up.

 

@Muddinfun @ucdbiendog

You guys are just plugging in the double-fused pig tail to an empty slot, right? Or are you also cutting and sealing the prongs?

Got my diode, 2 add-a-fuses soldered together and Odyssey battery and am looking to get this all right. Thanks!

 

Remove the 7.5A fuse shown in the pictures and install the diode in the direction shown in the pictures, so reads the same direction as the rest of the fuses.

The pigtail isn't required unless you want to install it.

 

the diode part is easy, but i wasnt able to find an empty slot for the other end, so i had to pull fuses and, using an ohmeter, checked what had continuity to the batter 12V. you can see the spot i used in the last picture, and just put the old 7.5A fuse in the other end of the add a fuse. make sense? if you can find an empty spot, no need to do this