I can start my car and log my evo 9 with evoscan. as long as I dont have the white connector connected. If I connect the white connector while the USB is connected to my laptop my car wont start. If i just have the white connector connected but not the usb then the car starts fine. I also cant read or write to the ROM.
disconnected the white connector wire and measureing voltage with the ignition ON. I get the 12V coming out the black connector wire to white connector. I get 5 volts comming off the ECU going to the white connector.
any idea what is causing this?