HP 8150n False "tray 2 open"

[Allan Mills]

When the tray is closed, the paper lift motor does it's job. The pick roller touches the paper, and then lifts the tiniest amount, above the paper. Everything seems fine, but it still thinks that tray 2 is open. I took the tray from another printer, and it had the same effect. I only need to know the sensor, or how the printer determines that tray 2 is open or not. Any ideas or help would be greatly appreciated.

Thanks in advance.

[cs_steve]

When the tray is closed, the paper lift motor does it's job. The pick roller touches the paper, and then lifts the tiniest amount, above the paper. Everything seems fine, but it still thinks that tray 2 is open. I took the tray from another printer, and it had the same effect. I only need to know the sensor, or how the printer determines that tray 2 is open or not. Any ideas or help would be greatly appreciated.

Thanks in advance.

There is a black lever at the back of the paper tray that senses door closure, the plastic is brittle and it is very common for that lever to break. (Usually breaks when a tray is closed with too much force.) The broken lever is part of the paper input unit, so the paper input unit needs to be replaced.

Here is a link to that part: http://www.printertechs.com/shop/hp-laserjet-8100-8150-paper-input-unit-rg5-4334-c4214-69017-rg5-4334-260-rg5-4334-000

[Allan Mills]

I decided last Friday to tear the printer down, and look for anything that did not look right. There is a circuit card that snaps in place, at the rear of the "fuser assembly". The card was in place, but not snapped in. That was my entire problem. The card has several optical sensors on it. I am sure it was loosened when I plugged the harness into it, that makes a 90 degree bend.

Thank you for your response.