asked Oct 14, 2002 at 11:55am
Hp HP LaserJet 4

paperjam sensor lj4mv

I have a HP lj 4mv. I was getting 50 service errors until I replaced the fuser. Now I can't get the printer to print from the lower cassette. The printer self checks but the pickup rollers don't spin. I can feed and print from the MP tray fine. I took the pick roller out and it has a magnetic clutch on it so I traced the power wires back to the board (dc controller?) and there are 4 wires, 2 to the main motor and 2 to the clutch. When I apply a voltmeter I get power to the main motor but when I send a test page it never sends power to the clutch.

So, it seems it's a probelm with that board. Is this one of the expensive item to replace?
Are there fuses on that board that might need replacing?

thanks for your help,