Dell 5110cn Service Manual page 226

Motor, Clutch and Solenoid
name (Diag. Code)
Rear Fan Motor (High)
(DO-3f)
Rear Fan Motor (Low)
(DO-40)
Rear Fan 2 Motor (High)
(DO-42)
Rear Fan 2 Motor (High)
(DO-43)
1) Turn on the power and enter the Diagnostic Mode.
2) Execute the DO-3f or DO-40. Put the hand to the left side
ventilation holes on the Rear Cover viewing from the back,
and confirm the air is inhaled into the printer.
The rotational speed of the rear fan motor is as follows.
DO-40 (slow speed) < DO-3f (high speed)
3) Press the "CANCEL" key to stop the test.
Rear Fan Motor
1) Turn on the power and enter the Diagnostic Mode.
2) Execute the DO-42 or DO-43. Put the hand to the right side
ventilation holes on the Rear Cover viewing from the back,
and confirm the air is inhaled into the printer.
3) Press the "CANCEL" key to stop the test.
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Chapter 2 Operation of Diag.
Confirmation procedures
Rear Fan 2 Motor
Ten02003KA
Ten02004KA