I have attempted to install 3 different black toner cartridges in my OKI c3400. I keep getting an error: "Toner cartridge lock lever is improper, drum missing, or toner sensor error. OFFLINE." I first thought it was the off-brand cartridge but have now spent more money and bought an original OKI toner cartridge. I have re-installed several times, checked all locking mechanisms, and cleaned sensors. Please help!

The locking lever may have dislodged (was not properly locked down).
Check the locking lever and firmly lock it down.

Check toner lock lever is in position - Seek attention of service person if restarting the printer does not correct the problem. See our How to Guide

Trata esto:
When installing the C3400n printer, or when replacing the toner cartridge, be sure to fully insert the toner cartridge into the image drum, and make sure the blue lever is pushed ALL THE WAY toward the back of the printer (fully locked position). If it is not fully closed (locked), a "toner sensor" or "toner empty" message may result. Note: (Picture at bottom shows incorrect position of locked toner cartridge that may result in either of these messages).

Installation Procedure of Image Drum and Toner Cartridge:

>> Insure the toner is fully locked, see photo below showing the correct and incorrect positions of the locked toner cartridge.

CORRECT (Fully rotated to lock position)

INCORRECT (Not fully rotated to lock position)

yuo have a leaky black toner cartridge
take out the cartridge and look for damage
aslo check the fuser for damge or leaks

replace any damaged cartridge

look this solution http://my.okidata.com/oki-faq.nsf/FAQCentral/C384D8F74A91CF6E8525765E0065F636?OpenDocument
here the solution for your problem
i hope that it's helpful .... bye

THIS SOLUTION IS FOR AN OKI C3400N ONLY

As I'm sure you know, that blinking amber light indicates that:

1. A toner lock is not fully "locked", or
2. A toner is empty, or
3. A drum is empty or near empty

The first question should be what does your C3400 monitor software tell you is wrong? I am assuming it said the black toner and/or drum needed to be changed - so you are fairly certain it is the black that is where the problem is? You may also have run the report from the printer that you get by pressing the "On-line" button and seen what is failing.

Assuming that is the case, and one or both of these signals an empty black toner, the problem may be in the new black toner cartridge. You can try this:

1. Make sure the toner "lock" on all toners is fully engaged - assuming they are

1. Open the top
2. Lift out the entire black assemble including the toner and drum components.
3. Keeping the assembly in the same orientation as you lifted it out, look on the RIGHT end.
4. You should see two metal contact points, near the top at about the same level as the top of the toner.
5. Just below these contact, you should see a small, rectangular hole - about 1/4" square.
6. If you look in there you may see what looks like a small piece of black plastic that covers the hole from inside.
7. If so, take a small pointed object (like a bent paper-clip) and gently reach in the hole and touch the small plastic piece on the inside that is covering the hole.
8. You should be able to gently lift that piece of plastic UP.
9. You may have to try lifting it a time or two, but it should stay UP if you have a new black toner installed.
10. Once you have it UP carefully reinstall the assembly.
11. Close the top and let the printer recycle.
12. You may need to try this a couple of times to get the plastic to stay up on your new toner.

So you understand, here is what may be happening. That little piece of black plastic actually sits in line with a sensor in the printer that monitors toner / drum levels. When a new toner is placed in, that piece of plastic should be UP, so the sensor can monitor the level. As the toner gets used, the plastic liece gradually falls down until it completely blocks the sensor - indicating the toner is empty. That is how the monitoring software knows how to signal you.

This has worked for me several times - most especially when I tried using non-OKI OEM 'compatible" toners - but no guarantees this will help you

Hi moneybaggz52:
Here is your problem.
Symptom:
When setting up a brand new C5100n or C5300n out of box, a toner sensor error is encountered.

The printer can display any one of the following errors:

543K: TONER SENSOR ERROR

540Y: TONER SENSOR ERROR

541M: TONER SENSOR ERROR

542C: TONER SENSOR ERROR
Cause:
This generally can be caused by two things.

1. The toner cartridge lock lever is not in the correct position.

2. The Transfer Belt lock levers are not in the correct position.
Resolution:

Check the appropriate toner cartridge lock lever (Shown below) and make sure that it is in the correct position.

CORRECT POSTITION INCORRECT POSITION


Check both transfer belt lock levers (Shown below) to ensure that they are in the correct position.

CORRECT POSITION


INCORRECT POSITION
Hopes this helps

Okay, I had the same problem with my C3300. I phoned the people i purchased from and this is what fixed it for me:

looking directly at the printer:
-open printer
-remove drum in question (the drum is what houses the toner cartridge) in my printer it is black.
-look on the right side of the drum & there is a little (approx 5mm x 5mm) hole that has a little panel that opens- push this up to open it.

-replace drum close the top and try printing.

I had to do this 2 times before it worked, but it worked.

Could very well be the sensor window. I suggest looking at the side of the drum on the right side and pushing a q tip into the opening. heres an older model thats sort of similar instructions. http://www.c3400.co.uk/index.asp?menumode=0&content=sensorerror
Also you can check the exact error code here. http://www.okic3400.co.uk/library/downloads/utilities/c3300c3400smv1115.exe

This error is toner not recognized
Follow the instructions for possible fix.

INSTRUCTIONS TO CHECK REFLECTOR OPERATIONS
(1) Open the poly bag, and take out the Toner-cartridge.
(2) Remove the tape to the position like the figure.
Tape
(3) Hold the Toner-cartridge horizontally, so that the Lever-sensor may go up and down
vertically.
Lever-sensor
(4) When it does not see the Lever-sensor like the figure, turn the gear in the direction of the
arrow, and it tries to see the Lever-sensor.
Gear
(5) Return the tape to former position.
(6) Put the Toner-cartridge vertically.
(7) Move Lever-sensor like the figure.
Lever-sensor
(8) Confirms the Lever-sensor is returned smoothly.
Lever-sensor
(9) Repeat (7) and (8), 3 times. The Toner-cartridge is wrong when the Lever-sensor does
not work from the position of (7) or when it does not return smoothly