by sperry » Sat Jul 12, 2008 10:18 pm
Bumping this old one because I just started playing around with RomRaider and ECU Flash on my '02 WRX.
I was seeing 2.11V with my jumper installed, even with a battery charger on the car. So I ended up hooking 12V straight from the battery to the jumper and was able to upload a ROM (with the headlights and A/C fans running to get the voltage back down).
Since this is a pretty inconvenient process to go through (trying to find enough stuff to turn on to drop the voltage) I grabbed a switch and a 100KOhm variable resistor (volume knob potentiometer) and built a little harness for the jumper block.
I used +12V off the illumination wiring (I'll move this to IGN later) and ran it to the switch, then from the switch to the pot, then from the pot to the single horizontal pin in the jumper block (no need to run the +12V to both pins).
Then I fired up ECU Flash and turned down the volume on the voltage gradually from 13V to the mid 12's. Things still weren't totally happy... for some reason at 12.68V it would complain it was too high, then I split an atom turning the volume knob the absolute smallest amount I could, and got a "voltage too low" warning at 12.60V.... WTH? But I came back to it after dinner, and tried again and the pot adjustment process went off without a hitch and I was able to upload my ROM.
All I know is, this is a real PITA to deal with... I wish there was an answer to why the '02 WRX's have this problem and what the correct solution is, 'cause manually wiring 12V into the jumper is retarded.