### BrianHall

asked Apr 30, 2006 at 4:49pm
HP LaserJet 4100

# LJ 4100 Fuser Testing

Does anybody have a diagram showing the test points for a LJ 4100 fuser? I have the HP service manual, but it doesn't show where they are; it just lists them.

Thanks,

Brian

Thanks,

Brian

With the connector at the bottom, you'll see 3 pairs of pins. The left set reads infinity. The center set reads 34 ohms and the right set reads 47 ohms.

I'm assuming that if the left set reads "open" instead of infinity that the thermo disk or temp sensor is faulty and that if the other 2 sets are reading ok that the heater is ok. Is this correct and if so where can I get a replacement sensor?

Open is the same as infinity.

Shorted would be 0 ohms, the opposite of infinite resistance.

Shorted would be 0 ohms, the opposite of infinite resistance.

HP LaserJet 4100