I just installed a new HO alternator and it seems like I'm not getting the full power out of it that I feel I should. I noticed in Merlin's Ecuflash tuning guide that there is an alternator charge current map but I can't find it for the life of me in ecuflash. Anybody have any idea where I might find it? Merlin's guide page 123 section 10.12 if you want to see what I'm referring to. Thanks

 

Is that physically possible? I can't recall any wires from the ecu to the alternator.

 

Answered my own question with research looks like the ECU does connected with pins 33 and 41 for an evo 8. So it could/does but i don't think anyone's looked for the table.

Its probably a PWM operation by the look of the config

 

Pwm?

 

pulse width modulation, i'm guessing

 

pulse width modulation signal its like a wastegate opening and closing the signal ground rapidly.

I'm thinking it could be found just no one took the time since this isn't a common issue.

 

Gotcha. Thanks guys

 

Looking at the diagram doesn't seem like the ecu would stop a high current alternator from running right. Its only supposed to control voltage drop at it looks like lower rpm conditions.

I could disassemble it i suppose but it will be hard to find out which one it is

 

I could be way off, but I was looking through the auxiliary engine functions portion of the code and I may have found the tables.

96530006
Alternator Charge Current: Sub_19EC0
Values: 4655
Engine Speed: 6940
Engine Load: 695E
I have it labeled as an unknown PWM output that can be logged through MUT8E.



G-Terminal Dead Zone: Sub-21354
Values: 46B6
Engine Speed Axis: 664A
Log through MUT8F

 

I was hoping to bump the values a bit in the lower rpm range. The alternator I have seems to lag a bit at lower rpm but hopefully the smaller pulley I pulled off the oem alt will make the difference I'm seeking. I was hoping I could just change the values instead of pulling the alternator out again but no such luck.

Roadspike. A few pages ago I offered you my vehicle to test your SD maps. I guess maybe you didn't see my post. Pm me I'd you're interested.

 

Sure test any of them you want and let us know the results

 

4xforce, what rom # did you want the charge map for and I will see if I have its address.


<scaling name="ChargeCurrent" units="Alternator Charge Current - Ampere" toexpr="x*80/256" frexpr="x*256/80" format="%.1f" min="0" max="255" inc="1" storagetype="uint8" endian="big"/>

<scaling name="AltDeadZone" units="Charge Efficiancy %" toexpr="x/2.56" frexpr="x*2.56" format="%.0f" min="0" max="255" inc="1" storagetype="uint8" endian="big"/>


<!-- *** Alternator - 9417008 *** -->

<table name="Alternator Charge Current" category="Alternator" address="4643" type="3D" swapxy="true" scaling="ChargeCurrent">
<table name="Load" address="71d0" type="X Axis" elements="9" scaling="Load16"/>
<table name="RPM" address="6106" type="Y Axis" elements="10" scaling="RPM"/>
</table>

<table name="Alternator G Terminal Dead Zone" category="Alternator" address="46a4" type="2D" scaling="AltDeadZone">
<table name="RPM" address="6106" type="X Axis" elements="10" scaling="RPM"/>
</table>

 

Thanks Merlin. Rom# 88590715

 

Looks like I have the right table, but my load is different. The load axis looks to be based off some other load variable?

Anyway until somebody knows the correct load variable, here is what I have.

96530006

 

^03whitegsr, I really suspect your load and rpm scale is correct, I used scaling from an Evo6, found a couple of years ago.

This snipit uses 03whitegsr's scaling

<!-- *** Alternator - 88590015 *** -->

<table name="Alternator Charge Current" category="Alternator" address="40b3" type="3D" swapxy="true" scaling="ChargeCurrent">
<table name="Load" address="6f7e" type="X Axis" elements="9" scaling="Load16"/>
<table name="RPM" address="6f60" type="Y Axis" elements="10" scaling="RPM"/>
</table>

<table name="Alternator G Terminal Dead Zone" category="Alternator" address="4114" type="2D" scaling="AltDeadZone">
<table name="RPM" address="6b7a" type="X Axis" elements="10" scaling="RPM"/>
</table>