Alternator Control problem
 

I'm running a MS3PNP (for an MSM) and am having a heck of a time figuring out alternator control. Currently, my alternator is pushing 15.3V all the time. Tunerstudio reads 15.3V and that checks out with the voltage read from my cigarette lighter plug.

Here is the setup. Connector pin for field control is 3M. Voltage sense from alternator is 4T.

Info (things I've tried):
1. Pull the plug into alternator. V=12V
2. V on field control pin (which is wired from PWM3) = 0.9V when output polarity is set to INVERTED. Tunerstudio reading 15.3V
3. V on field control pin = 5.3V when output is set to NORMAL. Tunerstudio reading 15.3V.
4. Change "charge mode target voltage" or "run mode target voltage", no change (15.3V).
5. Turn OFF alternator control. no change, 15.3V
6. Change any of the control mode "types" and no change.

So this is weird, because it is clear the circuit does something. Because unplugging kills it. But no settings (including OFF) does anything to affect the charge voltage. And, when that PWM3 output is 0.9V or 5.4V, no change!

Anyone have any suggestions?

bump to see if Ben or Matt or Brain or Someone out there can help!

email websales@diyautotune.com

IIRC early versions of their PNPs the alternator control was hardware controlled, not software.

Is this something that would be completely trumped by using the WestFieldMX5's adapter board?

I use a westfield design and it works great

it's basically that inside the case... when did you buy it?

This is DIYAUTOTUNE's MS3PNP (for MSM) that was purchased 1.5 years ago.

I went ahead and ordered WestfieldMX5's alternator control board. Thanks guys.

have you ever just tried changing the target voltage?

you should power cycle when you make changes to it.

yes, I've changed the target. No change. Seems silly to do it, but I'm just going to head the daughter board direction.

Not silly at all, it just 'works'.

To wrap up this thread (I hate open ended threads!).

What a pain in the ass. So after all this heartache, the problem was simple. I didn't know there was such thing as an internally regulated version of the alternator.

My original alternator worked fine. But I bought a complete used engine (VVT) and the previous owner put an NA internally regulated alternator on it... ugh. So I was trying to make the MS3 or the Westfield control board try and control it. Which sends like 0-5V or PWM or something of that nature. So that alternator was just pushing 15-16V all the time.

I switched back to my original alternator, but by then I had already burned up the Westfield with all my poking and prodding. So I switched back to the NA alternator thinking the old was busted. Then realized my folly and SWITCHED BACK to the old alternator. FINALLY!!

Got the MS3 working with the original alternator after about 5 swaps back and forth between many many combinations of parts and strategies...

Faith in MS3 is restored to the universe.

F man, I actually thought about asking you if you had an NA alternator.... sorry dude.

Mudflap, did you finally get this to work with the Westfield board or with the MS Alternator Control functionality?