Lexmark 7300 Series, Service Manual

Page: 33 / 88

4418-X6X
Diagnostic information
2-13
Service checks
Carrier transport service check
Unit/Problem Action
Carrier Transport
Motor Check the carrier transport motor connector J10 on the
system board. If it is connected, check for
approximately 30 V dc on pins 1 and 2 or at the wire
connections located on the rear of the carrier transport
motor. If the voltage is incorrect, replace the system
board. Go to
“System board removal” on page 4-14 .
If the voltage is correct, check the motor for binds or a
loose motor pulley.
A noisy or chattering motor or a motor that fails to turn
can be caused by:
• A broken circuit or short-circuit in the motor
• A bind in the carrier transport mechanism
Disconnect the carrier transport motor cable J10 from
the system board, and check for 15 ohms between the
two wires on the carrier transport motor. If the reading
is incorrect, replace the print engine. Go to
“Print
engine removal” on page 4-17 .
Carrier Guide Rod Clean and lubricate the carrier rod.
Lubricate the carrier rod and the carrier rod bearing
surfaces with grease P/N 40X0179.
Encoder Strip Verify that the encoder strip is installed correctly and is
free of grease or dirt. If the encoder strip is not installed
correctly, it can cause the carrier to slam against the
side frame. If the encoder strip is damaged, replace it.
Go to
“Encoder strip removal” on page 4-16 .
If the encoder strip and all connections are okay, but
the carrier slams the side frame, replace the system
board. Go to
“System board removal” on page 4-14 .