HP 3180 all in one printer gives error that paper is not present, yet tray has paper. Check paper light blinking, and E in printer display. Performed "hard reset" as shown on HP website, does not help.

Attention light is blinking
This state can be reached in
the following circumstances:
?Paper tray is empty
?Door open
?Paper jam
?Misfeed from tray

1.Verify that the print cartridge is present and that the print-cartridge door is closed correctly.

2.Verify that media is present in the input tray.

3.Clear any jams and perform paper-path functional checks.

4.Make sure that the interlocks are operating correctly.

To reset the printer after a jam, press the GO button

This link gives U full information about the control panel errors.. Pl go through it before replacing consumables..
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00476294&cc=us&dlc=en&lc=en&product=1146331#N1316

LED pattern Possible Problems and Solutions
Your system has some problems. If this problem occurs,
contact your service representative.
On Line/Error LED
lights red
• Paper jam occurs. To solve the problem, see "Clearing
Paper Jams" on page 5.6.
• The front cover is open. Close the front cover.
• Paper tray is empty. Load the paper in the Tray.
• The toner cartridge is out of toner. Remove the old toner
cartridge and install a new one. See "Installing the Toner
Cartridge" on page 2.4.
• You pressed the Cancel button while the printer is
receiving data.
• In Manual Feed mode, there is no paper in the manual
tray. Load paper into the manual tray.
• If the printer is receiving data, the On Line/Error LED
slowly blinks green.
• If the printer is printing the received data, the On Line/
Error LED blinks green fast.

Switch off & on once the printer, load papers in both trays, go to system choose file ask to print, when dialog box appears go to properties, select tray2., the shoot print, check its printing or not. If its printing problem in tray1 paper sensor,clean it.Reason why its not taking from tray 2. In menu settings its selected default tray as tray1. if no paper present in tr1 printer ask to press OK choose another tray to print, during this period indicating error.Best to do: clean all paper path sensor tray1 and tray 2 to prevent further errors... Pl revert..best of luck..

Attention light is blinking
This state can be reached in the following circumstances:
? Paper tray is empty
? Door open
? Paper jam
? Misfeed from tray
1. Verify that the print cartridge is present and that the print-cartridge door is closed correctly.
2. Verify that media is present in the input tray.
3. Clear any jams and perform paper-path functional checks.
4. Make sure that the interlocks are operating correctly.
To reset the printer after a jam, press the GO button.(Green Button)

if the light is blinking it means
1. either the cartridge door is open
2. or paper tray is empty
3 or paper is misfeed
4. or paper jam


Verify that the print
cartridge is present and
that the print-cartridge
door is closed correctly.
2. Verify that media is
present in the input tray.
3. Clear any jams and
perform paper-path
functional checks.
4. Make sure that the
interlocks are operating
correctly.

If you have a error code on display please respond. I can give you more detailed information.

If not, make sure that the print job that you are sending to the printer is for the same size paper that is present in the paper tray. Also, check that the tray is adjusted properly to the size for the paper that is present.

You could try running an internal print job to bypass the settings.

CAUSE: This error message indicates the paper present sensor flag in one of the trays does not detect paper in the tray. This could be caused by one of the following:

• A broken sensor flag
• The tray paper guides being set too close and restricting the paper from being pulled
• The tray is not lifting

SOLUTION: Follow the steps below to determine the cause of a false TRAY X EMPTY message. Tray 2 empty

1. Verify there is paper in the tray.
2. Open the duplex unit access door just above Tray 2 on the front of the printer.
3. Check the black-paper present flag by looking in through the duplex access door.
4. Open and close Tray 2 and observe the tray lifting looking through the duplex unit access door.

The tray lifts but the error is still present

1. Inspect the paper present flag on the PIU located just behind the pickup rollers. Ensure the flags are present and not damaged.
2. Remove the tray guides from the tray and reseat them. Ensure the guides are seated correctly and are in the correct slot for the size paper in the tray. Add paper to the tray and try printing again.
3. Try another known good tray, if available.

The tray does not lift and the error is still present

1. Remove the tray, remove the paper in the tray, and inspect the lifting plate in the tray for damage. Ensure it will lift freely by hand.
2. Try another known good tray if available.

Tray 3 empty

1. Verify there is paper in the tray.
2. Remove Tray 2.
3. Open and close Tray 3 and verify it lifts by observing through the Tray 2 cavity.

The tray lifts but the error is still present

1. Inspect the paper present flag on the PIU located just behind the pickup rollers. Ensure the flags are present and not damaged.
2. Remove the tray guides from the tray and reseat them. Ensure the guides are seated correctly and are in the correct slot for the size paper in the tray. Add paper to the tray and try printing again.
3. Try another known good tray if available.

The tray does not lift and the error is still present

1. Remove the tray, remove the paper in the tray, and inspect the lifting plate in the tray for damage. Ensure it will lift freely by hand.
2. Try another known good tray if available.

Tray 4 empty

1. Verify there is paper in the tray
2. Open Tray 4 and check for an extra **** of paper stored on the left side of the tray. This can cause the tray to stall while lifting and result in a tray empty message.
3. Defeat the interlock in the vertical transfer unit (VTU). Open and close Tray 4 and watch the tray lift through the VTU door on the lower-right side of the printer.
   NOTE: Follow troubleshooting steps for Trays 2 and 3 when working with the 2 X 500 sheet-input tray.

The tray lifts but the error is still present

1. Check the tray guides to ensure the guides are seated corrected and are in the correct slots for the paper size in the tray.
2. Inspect the paper present sensor for damage.
3. Check for any broken plastic pieces in the tray that may be a broken sensor flag.

The tray does not lift and the error is still present Defeat the VTU interlock on the right side of Tray 4. Open and close Tray 4 and observe the tray lifting.

check for paper jam if any or p head or cartridge indication for replacement
some symbol my blinking in display for user attention

this also indicate for error in plotter check for display icon and if you find any special icon other than normal screen as earlier, it will give information like paper with X mark ( no paper in tray )or paper jam ( two circle with Z mark )
or may be some screw driver and spanner X mark that can decode to give reason for LED blinking

if you get tool X mark check for ink level box in each row to check error code, its would be 6 numbers of rows and each row may some box
need to check and confirm to verify the error code

swap trays and test - if OK then your tray is set up wrong. remove paper and check that it is set for letter. also check the small switch (if there is one) on the Right hand side of the tray that maybe set to customer - change to standard. compare trays so they look the same - and check the settings in the menu for letter / plain on both trays