tuning help!
 

so, today, knucklesplitter came to reflash my ecu via opensource. well we ran into this error where it kept saying that the programming voltage was too low. it was reading something like 4 volts without the jumper connector connected, and like 1. something when it was connected. when he would do a test write, it completed with no problems, then, when he tried to actually write to the ecu, ERROR anyone know whats up with this?

I think the data cable may be missing the flash pin or it is not making good contact for some reason.

I assume your car battery is fully charged.

You have a 2002 wrx, don't you? It's a known bug w/ the '02 ecu.

There are all sorts of posts about it on the open source tuning forums. One partial solution is to supply 12v straigt from the battery to the jumper, but even that is inconsistant. I actually built a circuit with a potentiometer in it to be able to tweak the voltage to get mine to work.

I wish Matt has mentioned what he was working on when he borrowed my cable, I would have explained what's up with the 02 ecu!

ok, so i looked up on openecu.org forums. there is an older thread where they were talking about jumpering 12v from battery to some pin, or the jumper block. then they said the "correct" side of the jumper block. its not very clear. can someone clarify?

http://www.tactrix.com/images/0203_W...ector_smwm.JPG
there you go..
I have one BTW

^Did you ever get that Evo tuned?

I actually tune now... so it is tuned...LOL

That doesn't supply power from the battery to correct the 02 ecu issue. Using that is what causes the improper voltage errors.

Unfortunately, I don't remember off hand which pin you apply the voltage to (and I'm out of town right now so I can't go look), but I'm pretty sure you can just try both pins until it works since one pin is the input and the other pin is supposed to be 12v anyway.

If putting 12v to the jumper results in an over voltage error, you can try turning the lights on or running the a/c fans. And if that's still not enough, you can add a resistor to the line, which it what I did with that pot so I could adjust it until it works.

Or you can just get an 03 ecu that doesn't put out the incorrect voltage to the jumper to begin with.

tune is complete, well almost. anyway, i just made a jumper and we got it done. thanks guys.

We installed the Subaru jumper plug (just like the Tactrix one) and then applied raw battery voltage from the battery terminal to a t-pin stuck into the jumper plug. It flashed on the first try after that. Kinda a PITA.