Sense is the "S" wire on the schematic.
What location are you putting the diode? Engine Bay Fuse Block or Dash Fuse Block?
Charge Ckt
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Sense is the "S" wire on the schematic.
What location are you putting the diode? Engine Bay Fuse Block or Dash Fuse Block?
It appears the 100 series puts a 7.5A fusiable link in front of the alternators Sense wire. According to instructions, it is this fuse that gets replaced by the diode.
On the 80 series, the fuse location, 7.5A Charge, is on the Charge Light Warning circuit. It is not on the Sense Line circuit.
You could add the diode to where the Sense line connects at the FL AM1 1. 2 5B near the battery. Just add an inline fuse holder.
On the 80 series, the fuse location, 7.5A Charge, is on the Charge Light Warning circuit. It is not on the Sense Line circuit.
You could add the diode to where the Sense line connects at the FL AM1 1. 2 5B near the battery. Just add an inline fuse holder.
I don't think I would go that route as FL AM1 feeds a variety of downstream circuits so you would need a diode that can handle the current.
I would install it close to the alternator if I would do this at all, which I would not.
COS80
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I wonder why it's a diode at all. Just because it can be had in the form factor of a fuse? I can't imagine what the directionality of the diode would have to do with anything here... seems it's just the resistive effect in the right direction... so would a resistor do the same thing?
I don't think I'll experiment any further with this. I do have to rip out the entire charging system to crimp the connectors, so maybe I'll redo some of that wiring, if I identify something to change, I'll do it at the same time.
That leaves me back at square one. What little searching I could do for custom/adjustable regulators, today, yielded nothing of value. Happy to hear any input or advice.
I don't think I'll experiment any further with this. I do have to rip out the entire charging system to crimp the connectors, so maybe I'll redo some of that wiring, if I identify something to change, I'll do it at the same time.
That leaves me back at square one. What little searching I could do for custom/adjustable regulators, today, yielded nothing of value. Happy to hear any input or advice.
No worries.
We all miss things. It is just something I came across previously when studying Toyota EWDs.
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It's a diode because the diode has a voltage drop in the forward direction that is likely around 0.5 to 0.7V. So, it basically would make the sense voltage look 0.5 to 0.7V lower than it actually is. So, the regulator will increase the alternator voltage by 0.5 to 0.7V to get it to the voltage it wants to regulate to. So, the diode in effect will increase the charge voltage to the battery by 0.5 to 0.7V.
There's companies that sell this magic diode thing for many dollars...
It is a hack.
cheers,
george.
It absolutely can, and would be cleaner if wired in the harness for the sense wire.
The diode thing exists simply as a plug n play alternative for the masses. Most folks can't solder and crimp, but they can handle swapping a fuse for a diode from a GM that simply plugs in and works.
This makes me want to order some connectors and make a plug n play harness that goes between the factory harness and the alternator and experiment...
I just ordered the connectors and pins....I'll see if I can let the smoke out of something expensive!
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NO - a resistor has a voltage drop dependent on the current through it. How would you choose the resistor value in this case? What current would be flowing through it? V = I * R. What is the I in this case?? A resistor is NOT what you want to use in this application.
A diode has a relatively fixed voltage drop that is mostly independent on current through it, certainly minimal difference between say 100uA and 100mA. Of course there will be temperature dependence and some current dependence. It is a hack.
There are different types of diodes (silicon, schottky etc). A silicon diode will be in the 0.5 to 0.7V range. A schottky closer to 0.2V to 0.5V. You can also put diodes in series. The issue is that the voltage drop is not very precise. It is a hack...
cheers,
george.
A diode has a relatively fixed voltage drop that is mostly independent on current through it, certainly minimal difference between say 100uA and 100mA. Of course there will be temperature dependence and some current dependence. It is a hack.
There are different types of diodes (silicon, schottky etc). A silicon diode will be in the 0.5 to 0.7V range. A schottky closer to 0.2V to 0.5V. You can also put diodes in series. The issue is that the voltage drop is not very precise. It is a hack...
cheers,
george.
As @george_tlc says: THIS IS A HACK. I did this purely for experimentation purposes. I have a total of 30 seconds of run time on it, so no idea if it's a lasting hack or not....
I ordered some connectors and did some dirty things
I ordered some connectors and did some dirty things
Got the expected 0.5V increase in charge. Time will tell if this works or not. This was on a cold start so the alternator was already cranking out 14.1V, where when it's warmed up I usually only see 13.6-13.8. Immediate shutdown, and then I plugged in my little patch harness between the alternator and the factory harness. Restarted 2 mins later, and got the 0.5V bump. Diode is on the sense wire at the alternator. YMMV
Yes, GM diode in the fuse holder. So far, no ill effects- even with all accessories powered up. The diode is only on the sense wire at the alternator, so in theory nothing else should care.