error code " 2000-0411"

I have a dell inspiron 1721 it had a bad fan, so I replaced it and checked other hardware.

everything looked good.
Upon putting the laptop back together I am getting " error code 2000-0411" touch pad not detected.
also upon booting it hangs on "preparing to enter setup" I've checked keyboard, touchPad.
Completed Diagnostic test, this is the only error. Any Ideas?

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