if i take the battery lead off un plug the ecu for more than 30 mins am i right in thinking the ecu light will not come on when i plug it back in . its not on now just dont want it to come on when i plug it back in . been told if i leave the battery lead off for more than 30 mins should be ok car is 1992 wrx import

thanks

 

Should be fine mate. But to be on the safe side I'd plug the ECU in before you connect the battery. I had my ECU out on plenty of occasions and never had a dash light on..

 

thanks mate