HP 5L fuser resistance

[Chris]

What should the resistance of the fixing heater be? This one measures about
34 ohms.

Chris

 

[Gert van den Heuvel]

What should the resistance of the fixing heater be? This one measures
about 34 ohms.

Chris

Hi Chris,

The resistance should be 30 +/- 10 ohms. So 34 ohms sounds fine.


HTH,

 

[Chris]

Thanks. The top and bottom lights come on when the button is pushed. I also
watched the voltage to the heater. It's only on for a second or so but it
looks to be around 100V. If the heater is good and getting power, is the
temp sensor at fault?

Chris

 

[Gert van den Heuvel]

Thanks. The top and bottom lights come on when the button is pushed. I
also watched the voltage to the heater. It's only on for a second or
so but it looks to be around 100V. If the heater is good and getting
power, is the temp sensor at fault?

Chris

Yes, it's very well possible that the sensor is defective.
Top and bottom lights means a fuser error. We already know that the heater
is OK, so remove the thermistor (temperature feedback) connector and
measure the resistance between pins 1 and 2. Normal resistance is 440K ohms
+/- 30K at 20 degrees C.

 

[Chris]

I found a fuser from a Canon CFX-L3500 fax and it works. I think the part
numbers are different but are the specs similar?

Chris

 

[Gert van den Heuvel]

I found a fuser from a Canon CFX-L3500 fax and it works. I think the
part numbers are different but are the specs similar?

Chris

Yes, it's very well possible that the sensor is defective.
Top and bottom lights means a fuser error. We already know that the
heater is OK, so remove the thermistor (temperature feedback)
connector and measure the resistance between pins 1 and 2. Normal
resistance is 440K ohms
+/- 30K at 20 degrees C.

I dunno. I don't have the specs for that fax. But you could measure the
resistance of the heater and the thermistor and check if those are within
the specs of your HP.