Lexmark CX310n Service Manual page 56

Actions
Step 7
Turn the printer off, and remove the rear shield. See
on page 221.
Verify the cable is correctly connected to JFUSES1 on the controller board
and to the sensor.
Is the sensor cable properly connected?
Step 8
Turn the printer on, and check the values at JFUSES1:
Pin 8: Ground
Pin 9: +3.3 V dc
Are the values approximately correct?
Yes
Go to step 8.
"Rear cover removal"
Replace the duplex
sensor. See
sensor removal" on
page
Diagnostic information
56
No
Reconnect the cable. If
the problem persists,
then go to step 8.
Replace the controller
"Duplex board. See
board removal" on
244. page 239.
7527
"Controller