Alternator Voltage Booster

[uHu]

Now, for adding a diode in the 100, I found that there is a short-pin in series with the alt-s fuse, so that it is possible to just pull out the short-pin and push in the diode, as long as it comes in a package that fits the socket.
This short pin is in gasoline and diesel vehicles from 7/2002 production, not the earlier years, and sits in the middle of the fuse-box in the engine compartment. It's called Short Pin B, and is a long, black latch across the two rows of fuses. Now, the problem is that this long black bar consists of two short-pins in one package with 4 connectors. One (the interesting one) between the two end pins (pin 1 - 2) and the other between the two inner pins (3-4). The second short-pin/latch is in series with fuse NV-IR, which is the middle fuse in the rear row, next to this short-pin, in some vehicles numbered 6 and in others fuse #10.
In my Owner's Manual, the fuse NV-IR is marked "No Circuit", so I suppose I can just forget about the second part of that short-pin-bar. I haven't been able to find out what NV-IR is. Does anyone know?

That was what I could glean from the manual and diagrams. When looking at the reality, in my 2004 HDJ100, I found that the interesting short bar/pin is the centre portion of the four-pin thingy, not the outer two pins as stated above.
The fuse that says NV-IR in the manual and in the BE-diagram actually says CDS FAN in the lid of the box. Looking at the diagrams I found "Condenser Fan", which is found in 1fz-fe and 1hz models only, after 7/2002. So I suppose I can live without that link and circuit.

Now, a problem is that the same short-pin that supplies the sense voltage through fuse Alt-S, also supplies hazard/turn indicators. I can still put a diode there, but it will have to be able to take the load of all the blinker bulbs, which is about 10 amps.

I tried it out today, and found that my charge voltage went up from 14.3 to 15 volts, which would be ideal for the calcium batteries.

One thing that hasn't been discussed here is that with a higher system voltage, all "consumers" would have a higher voltage as well. The result is better light output, and shorter bulb life. Don't know how much it would mean in practical terms, but 0.7 volts is a considerable increase.

 

[f5driver]

I installed the voltage booster. It seems to increase the volts about .5 volts across the board. The alternator now puts out 14.6 vs 14.1 immediately after engine start and 14.1 vs 13.6 continuous. My dual battery set up is achieving a higher state charge for running the fridge.

 

[AimCOtaco]

I just installed a home made voltage booster as my system was generally about 13.4 - 14.2 running and my optima's were not lasting as long as they do in another Toy' with higher voltage. Optima (AGM battery) recommends 14.0-14.8 or so which lead me to want to try this and see if my battery's last longer. I think the optimas were not reaching full charge with just 14.2 max from the alternator.
I used a circuit tap that is designed to add a fused circuit from a fuse panel without bypassing the original circuit fuse. I just chopped the output pin down enough that I could make the assembly narrow enough for the battery fuse block on the LC and used a basic 6A rectifier diode and a couple of solder joints. Configured this way the rectifier is in series with the ALT-S fuse. Here it is done and in (5a fuse for bench test only):

I had considered a wiring modification due to the tight space but this worked great and can be returned to stock in 1 minute if needed. Now I seem to be running between about 14.0 and 14.8 depending on operating conditions. This should keep things brighter and pulling lower current, the radios seem very happy as well. Optimistic that I'll get longer battery life but time will tell on that. Not a bad mod for $10 and a few minutes cutting and soldering.

 

[crimsonaudio]

I had considered a wiring modification due to the tight space but this worked great and can be returned to stock in 1 minute if needed. Now I seem to be running between about 14.0 and 14.8 depending on operating conditions. This should keep things brighter and pulling lower current, the radios seem very happy as well. Optimistic that I'll get longer battery life but time will tell on that. Not a bad mod for $10 and a few minutes cutting and soldering.

That's fantastic.

 

[matt12]

Old thread but for the records and future readers ...

HKB Electronics - Toyota

 

[SanDiegoCruiser]

I’m looking at doing this mod. Is anyone selling a kit for a 99 LC 100 that’s not $50 for a single diode?

 

[AimCOtaco]

@SanDiegoCruiser I'll make you one like mine for just 49.95!

Seriously, you can make one easy man but send me a PM if you want me to make one for you.

 

[SanDiegoCruiser]

@SanDiegoCruiser I'll make you one like mine for just 49.95!

Seriously, you can make one easy man but send me a PM if you want me to make one for you.

Haha, I just went ahead and purchased it. Time = money and these days my time is limited! Thanks for the offer.

 

[Tanner Gonzales]

Why is it that the truck still runs and charges without that fuse in at all?
Thanks and which way is the flow not seeing result and I feel like I’m missing something.

 

[Tanner Gonzales]

@aimcotatco

 

[AimCOtaco]

Tanner,
Your truck will start and run on the battery until it dies but I don't think the truck will charge with that fuse out, not sure though.
I have not tested it but if it indeed does charge without the fuse then it charges because it detects a low voltage (0v) on this sense line where normally it would stop or slow charging when the voltage is high enough.

Which is to say:
If it's connected to 16v it would stop charging.
If it's connected to 12.5 v it would charge.
If it's connected to 0v ... I don't know, might charge (but also lead to overcharging so hope it fails safe).

 

[Tanner Gonzales]

Yes of course, lol I dont know what I was thinking I have a deep cycle optima yellow so that’s what’s going on.
Thanks appreciate it I do see a half volt more on my volt meter at all times.
Appreciate the response.

 

[Tapage]

@SanDiegoCruiser I'll make you one like mine for just 49.95!

Seriously, you can make one easy man but send me a PM if you want me to make one for you.

Not sure if this offer it's still valid or will be extended to others MUD members but if not can you share where you got the fuse older you use .?

 

[Pucker5]

Old thread but for the records and future readers ...

HKB Electronics - Toyota

Anyone have this? Does it work? I want to get a bit more voltage to my agms, particularly my battery that my stereo amps draw from. They are hc capable

 

[Cola]

Anyone have this? Does it work? I want to get a bit more voltage to my agms, particularly my battery that my stereo amps draw from. They are hc capable

I have this and it works as advertised. 0.5 volts higher than the stock fuse. Been using it for 6 months with no problems. Run my fridge 24/7 and can leave my truck for close to 5 days with my 31 and it'll still start

 

[Pucker5]

I have this and it works as advertised. 0.5 volts higher than the stock fuse. Been using it for 6 months with no problems. Run my fridge 24/7 and can leave my truck for close to 5 days with my 31 and it'll still start

Do you have the mk1 or mk3?

 

[dogdaysindurham]

For my 05 I have the MK3 for the past 3 years, no issues. Has get my dual Group 65 AGMs pretty happy. I do use a dedicated AGM charger once every 2 weeks to charge up both.

 

[Cola]

Do you have the mk1 or mk3?

Mk3. Figured that shipping was 40% of the cost so I ordered two when I did and always have one spare.

 

[Tapage]

They also have the adjustable version for twice the price of the MK3 ..

Must be a US company who made them and save the 26 shipping cost for a fuse ..

Maybe a group buy and split the shipping costs .?

 

[CORunner]

They also have the adjustable version for twice the price of the MK3 ..

Must be a US company who made them and save the 26 shipping cost for a fuse ..

Maybe a group buy and split the shipping costs .?

I'd be down for a group buy.