try to remove the chip first and cleaning all the points , or change the wires your using, and try to see the dms3 web they have a good points for you to look,
it did happen to me when i was installing it on my friend ps2 so i did remove all the wires and cleand all the points with a cleaning flowyed, try to see if the ps2 is working without the chip if ok then try to install it again.