Hello, i have a Problem with my Canon dr 9050c. If the scanner starts the paper-tray move correct up and down. If the Scanner get a Scanjob from pc than the tray don't lift up. it sounds like the motor only vibrating but nothing happend. I orderd a new motor, a new sensor ( the sensor who realize that the tray is down) and new cable for they tray but the Problem is the same. I installed the scanner on a new PC to elimante Problems from the pc. I also use the Canon diacnostic Software: DRUnificationTool and there the same Problem. Only the "tray Unit paper detect Sensor" seems to be active all the time. Have anyone tips for this Problem? Big Thx

Question edited for full 'make model (what it is)' and typo.

If the roller spins, clean it with soapy water on a cloth. If the rollers aren't turning, you need a Canon Service Centre for a pro machine.
https://www.usa.canon.com/internet/portal/us/home/support/details/scanners/document-scanner/imageformula-dr-g1100/imageformula-dr-g1100-production-document-scanner

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Remove the paper tray, remove the cables carefully. If you turn tray upside down, you will notice screws, remove them carefully. clean the 'golden finger' and ensure there are no staple pins. (Staple pins alter the circuitry). The gear wheel and the paper guide must be placed correctly so that it moves freely.

S. Mohan, India

It sounds like you diagnosed it.
The tray "paper detect sensor" thinks it has paper in it, and if it doesn't have paper in it...there's a problem with the sensor.
Take the tray off and inspect the sensor. Blow out around the sensor and it's PCB and make sure it is not out of position. Check the sensor lens for anything blocking it, and retest. If it still shows always on, then replace the sensor. Press the "count only" button to illuminate it, and press the "start" button. If the scanner works properly (tray lifts, pulls paper through the scanner, and counts it)...well then you have software or connectivity issue.

Hope that helps,
Scan-R-Store Scan Store provides service and maintenance contracts on all Canon Fujitsu...

IT could be a problem with the paper sensor. Please clean the sensor in the paper tray, it looks like a 'black dot' .
S. Mohan, Chennai, India

Irrespective of the position the tray has to go down on powering on. There is HP (Home position) sensor for the paper tray, under the tray. Check if it is okay. Also in the middle of the paper tray, there is a paper sensor, clean this with a damp cloth so that the does not 'assume' there is paper. If the scanner has paper, it will not go down.
S. Mohan, chennai, India

Clean the two 'black dots' in the paper tray, just under the roller. They are actually paper sensors. Try 'page counting'. If this works, the scanner is okay. If the problem still persists, try reloading the scanning software.
S. Mohan, Chennai, India

Disconnect the scanner from the Comp, Try 'page counting'. If the papers go through, then you know feed mechanism is okay. if the tray is not lifting, then you have a problem. Use Qumatool software and check if the tray is lifting. If the scanner tray if lifting then the motor is okay, if not, the lifting motor may need a check.If the motor is okay, but tray not lifting means the sensor in the paper tray is faulty. Check this out.

S. Mohan, Chennai, India

The scanner is assuming there is no paper. Just under the rubber rollers, in the paper tray there is a paper sensor. Clean that area with a damp cloth. Keep some papers and try "count-only". It it works then sensor is okay, else, you need to check the sensor.
S. Mohan, India

There is a paper sensor just under the rolers in the lifting tray. Clean the area thoroughly with a damp cloth. Keep some sheets and try ]count only'. If it works then the sensor is okay, then you can try your scanning. If it is not sensing paper, check the sensor or connections to the sensor.
S. Mohan, India

Michael, U can buy 9080C service manual at tradebit.com 9080C has no belt for lifting the tray. It has arm and a few gears. Ensure that the plastic gears are not deformed. Good Luck. Which version of Capture perfect do you use? 
S. Mohan