How to solve Toner Sensor Error on Oki printers

After replacing your Toner or Drum you get this message: “Toner Sensor Error”.

This error appears on these printers: C3200n, C3520, C9200...

Solution:


Possible Cause #1: Toner cartridge may not be locked into the Drum properly or the Toner/Drum unit may not be locked into the printer correctly.

Resolution: Check the Toner cartridge Lock Lever (Figure 1) and make sure it is in the LOCKED position:

Possible Cause #2: Error may occur if the plastic Shutter / Flap on the side of the Toner cartridge is fully or partially down blocking the Toner Sensor window (C3000 Series printers).

Resolution: Move the Flap upward and out of the opening to allow for the Toner Sensor to become fully exposed prior to reinstalling the Toner and Drum combination. This is a simple, easy step you can perform. (Ref. Figure 2)

The safest way to move this shutter is either with a toothpick or something plastic. Do NOT use a paper clip or anything metal to move the shutter. A metal object may short out the sensor making the Toner cartridge useless.

Left: correct position -Right: incorrect position

Possible Cause #3: The Drum or Toner may be defective.

Resolution “A”:
Remove the Toner/Drum assembly (without touching the blue locking lever).
Look inside the printer to locate the sensor for the Toner/Drum assembly.
Blow canned air into the sensor to clear out any possible dust.
Wipe the sensor clean with an alcohol wipe.
Re-insert the Toner/Drum assembly into the printer.

Resolution “B”:
Swap the Toner/Drum assembly (without touching the blue locking lever) with another Toner/Drum assembly (if available).
If the Error stays with the Toner/Drum assembly, then you can assume the Toner/Drum is defective.
Normally you would start by replacing the Toner first. If that does not resolve it, then try replacing the Drum.
If the Error stays with the same location, then you can assume the Printer is defective.