Introduction

Periodic cleaning is necessary to ensure that the printer continues to function properly throughout its life.

One area of the printer that must be cleaned periodically is the Overhead Transparency (OHT) and two-sided (duplex) printing sensor. The OHT sensor detects and ensures that the printer uses the correct print mode. The sensor also corrects for paper skew on the second side of the page during two-sided (duplex) printing.

The static discharge comb at the top of the printer also needs periodic cleaning. A brush to clean the static discharge comb is stored inside the front cover.

When to clean the OHT sensor

• The printer control panel reports that paper is being used instead of the desired transparency.
• The images on the front and back of the printed page do not align.

How to clean the OHT sensor

Figure	Step
Figure 1: Opening the top cover	1. Lift the top cover of the printer.
Figure 2: Opening the front cover and the transfer unit	2. Grasp the front cover and pull down, and then grasp the green handles on the transfer unit and pull down. 3. Remove the cyan print cartridge from the printer. CAUTION: Do not place the cyan print cartridge on the transfer unit while it is open. If the transfer unit is damaged, severe print quality problems may result.
Figure 3: Removing the OHT sensor cleaning brush 1- Location of the cleaning brush	4. Remove the OHT sensor cleaning brush from the base of the printer.
Figure 4: Cleaning area	5. Insert the brush into the base notch and brush from right to left four or five times. NOTE: Do not brush back and forth over the sensor. This will smear dust over the sensor and cause printer errors. 6. Replace the OHT sensor cleaning brush into the base of the printer. 7. Align the cyan print cartridge with the tracks inside the printer and insert the cartridge until it is completely seated. 8. Close the front cover, and then close the top cover.