An OKI printer can show many common errors, such as paper jams, low toner levels, etc. But there are some other errors that can be new to you. As a printer contains many internal parts, damage to any one of them would lead to certain problems, which your printer will show on its display. Hence, you need to understand the meaning and solutions of these errors. Let’s see what are these other errors. 

Issue 1: Poor Print Quality

The printer will not directly display “poor print quality.” It will print misaligned prints with random texts in faded color. When you print a document, you notice that half of the text is unreadable and faded. You can also find the text overwritten. In this case, you can follow these easy methods. 

Check the Toner Levels

Checking toner levels in an OKI printer is simple. However, it differs from printer to printer. Note that not all the OKI printers have a similar method for checking toner levels. 

Here are the general steps to check it: 

1. First of all, press the Menu button on your OKI printer. You’ll see Menu written on that button. 
2. Then, use the arrow keys to go to the Supplies/Information or Configuration option. The options depend on your printer model. Hence, if you’re not getting these options on your printer, refer to your printer’s manual. You can also Google a manual for your printer model. 
3. Now, press OK on the printer. 
4. Select the Toner levels from the available options on the printer and check the percentage of each ink toner. 

Replace the Toners 

If the ink toner levels are less than 10%, it needs to be replaced. Use these steps to replace an ink toner cartridge. 

Step 1: Turn off the Printer 

1. The first step is to turn off the printer by pressing the power button at its front. 
2. Then, disconnect the USB cables from the printer and remove the power cable from the wall outlet. 

Step 2: Open the Printer Cover and Release the Toner

The printer cover opens the place where the ink toners are installed. Hence, you should open that cover. 

1. To open the cover, slowly pull out the door, which can be located at the front or top of an OKI printer. 
2. Then, check the ink cartridges installed in a row. Usually, four cartridges are installed together. Their slots match the cartridge ink color. 
3. Slowly pull out the low-ink toner cartridge. 

As the printer doesn’t show accurate ink levels, you can also shake the ink cartridge after removing it from the slot. 

Step 3: Install the New Cartridge

When you have released the cartridge from the slot, take out a new cartridge and remove its packaging material. Then, it is ready to be installed. 

1. Take that cartridge and place it in the right slot. Check the label on the cartridge and slot. 
2. Then, fix it until it clicks into place. 

Step 4: Close the Printer Cover

Once you have installed the ink toner cartridge, you can simply push the printer cover. Now, you are ready to use your printer again. 

Step 5: Turn on the Printer 

Once you have installed the ink cartridge, you can connect the printer’s power cables back to the power wall outlet and press the power button to turn it on. 

Issue 2: Drum Unit Error 

A drum unit error indicates that the drum unit is damaged. This is an internal part of the printer that takes the ink toner and transfers it to the paper. When this drum unit gets damaged, your printer shows the “Drum Unit Error.”

In this case, you can simply restart your printer. However, a restart will only temporarily resolve the problem. Hence, you need to reinsert or replace the drum unit. 

(Note: Before performing these steps, please turn off your printer. To turn off, press and hold the power button, and remove the cable joining the printer to the power outlet on the wall. )

Solution: Reinsert the Drum Unit

Reinserting a drum unit resolves the drum unit error. Check how to reinsert it: 

1. First of all, open the printer cover at the front. Note: The printer cover can vary according to the printer model. Hence, it's best to review your printer manual. You can get the printer manual from Google. 
2. Then, you will see a unit attached to the ink toner, which is the drum unit. Remove the whole unit together. 
3. Now, fix the unit and bring it back into its place. 
4. Close the printer’s front cover. 

By reinserting the drum unit, you can fix this error quite easily. 

An OKI printer can show errors like fuser unit error, drum unit error, etc. Usually, the hardware-related errors that are caused by the printer’s internal parts need a replacement. For instance, the drum unit and fuser unit error shows a need to replace these parts. However, in some cases, restarting the printer and reinserting the unit can fix the error.