I have an 01 civic ex 4 door automatic I bought used from a kid he just put in an ECM/PCM right before I bought It but said it wouldn't go over 55 mph got it home tryed to scan test and I have no communication with any thing I thought maybe the ECM was bad because it was used then last nite the radio stopped working and the abs light came on and it died on me wouldn't restart long story short could the mcu b the cause of these issues?? Has any one had this problem ???

 

Sounds like there's either a multiplexer fault, or fried ECU.