2007 GMC Sierra Wiper motor?

Where are the wiper control PCB relays located. I thought they would be located next to the wiper motor fuse on the fuse box under the hood. Also where might the BCM be located that controls the wiper motor on my 2007 GMC Sierra SLE. Also if I have no visible warning lights like check engine lights would hooking it up to a Actron code reader even help or detect electrical problems like the wiper motor not shutting off w/ the key out of the ignition and intermittant wiper function not working?
Thank you,
Dave M