what does link error actually mean?

Question

when i try to scan, this is what i get: scan... pwm, scan...can, scan...kwp2000
scan...is09141, link error!
Now i have no check engine light, but i just put new top end gaskets in it. There should've been some codes already stored i had not erased yet.
Its running fine, i'm pretty sure everything is hooked back up the way it was before.
also the cooling fans are not coming on. fuses are good, checking relays now