Hp 4500 with fan error

Archived from groups: comp.periphs.printers (More info?)

Greetings all,

I have been working on an HP4500 with a 57.1 fan error. The book
indicates the little fan on the left side is at fault. I have replaced
the fan as well as the large fan on the right. I still receive a 57.1
error soon after powering up the printer. (both fans are not running)
My question is do I replace the main DC controller card or the card the
fan directly plugs into?
On a side note, a week prior to replacing the small fan I replaced the
large fan and it ran fast all the time until the 57.1 error showed up
permanently. I am going to try and disconnect the large fan as it may
be causing the problem.
The serial number for the printer is below "G"

Thanks
Jerry