5.Using a long cotton swap that is saturated in isopropyl alcohol, clean the top and bottom slit by inserting the swap into the opening from the input-side of the sensor (versus inserting from the user-end of the sensor).

CAUTION: Inserting the swap from the user-end toward the service-end may push debris into the slits. Insert the swap moving from the input-side toward the output-side direction. Do not wipe across the slits, as this will force debris down into the openings.

80 Chapter 5 User cleaning

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