"my chipped ECU doesn't work! Help!"

When you say "it doesn't work," what do you mean?

There are a couple of common problems encountered when chipping ECUs:

• Sometimes the CEL will come on and there will be a pattern of flashes indicating an error code present. See Checking Error Codes.
• Sometimes the CEL will come on and just stay on continuously. Attempts to jump the service check connector to check for code blinks fail. See Troubleshooting Solid CEL.
• Sometimes the CEL is not on, but the car still runs horribly. See Troubleshooting Operation?

This is a work in progress - please feel free to add your thoughts and experiences.

CAR DOES NOT WORK * First make it sure ECU ' s led is blinking at KOEO is seen ECU power OK. another way to find out ecu is powered and grounded when car is KOEO state measuring any sensor power example TPS sensor if you see +5V ECU is normally grounded and poweredi. if not. you dont seen ecu havent got power and ground. it s cause can be main relay near to dash. it is two relay on one box. Ater ignition is ON one relay is goes on and supply power to ECU afret ECU powered it Grounrded second relay and supply ground to fuel pump. you hear sound that fuel pump functional. MIL also goes off after 2 second.