getting code u1000 and u1001. replaced ipdm & ecm with used ones. still no CAN Communication

Question

getting code u1000 and u1001. Replaced ecm and ipdm with other used ones and the CAN Communication is still not working. The starter relay will not make the starter engage. I swapped the starter relay with another relay already. I also swapped the road light relay with the ecm relay on the ipdm. I'm Larry

Answer 1

if you swaped your ecm it will need to be flashed to probably reprogram it ..even if from same year make and everything. .i have ran into this a few time ..your computeris not sending any signals to the engine. ..