Troubleshooting Guide - Panasonic MC-CJ903-R747 Service Manual

3 Troubleshooting Guide

CONDITION CHECKPOINT
The motor doesn't CORD REEL PAR-
rotate. TITION UNIT
MOTOR
POWER
TROL UNIT
FUSE UNIT
THERMO
TECTER
ON/OFF SWITCH
1. The Motor
doesn't rotate.
2. The Power Con-
POWER
trol doesn't func-
TROL UNIT
tion.
P.C.B A UNIT
FIGURE
CON-
PRO-
CON-
CHECK METHOD
• Check the continuity at both
ends of the Plug and both ends
of the Lead Wire Terminal of the
Cord Reel Partition Unit. (Dis-
connection check)
• Check the continuity of the Lead
Wire connected to the Body
Partition Assy.
• There must be no problems
between the Cord Reel Assy
and the Body Partition Assy
(e.g. burns in the contact, entry
of dust).
• Check the continuity between
the terminals of the Motor.
• Confirm that the Motor can be
rotated by fingers without being
locked.
• Visually check for burns in the
Motor (e.g. burns in the coil).
• There must be no broken com-
ponents.
If they are normal:
(1) T1-T2: There is not continu-
ity.
(2) T1-G: There is continuity.
• There must be no broken foil of
the Printed Circuit Board.
• There must be no breaks in the
Lead Wires.
• Check if the Fuse has blown.
Causes of fuse blowing:
1. Overcurrent
2. Burn of the Motor
3. Short-circuiting due to incor-
rect wiring
• Continuity check.
• Check the continuity by press-
ing the ON/OFF Switch.
• Check that the Triac has not
been short-circuited.
If there is continuity between T1
and T2, then there is a problem
in the components.
• The resistance between A and
B must be switchable.
* See the circuit diagram
(6. Printed Circuit Board)
for the switch resistances.
4
REMEDY
• If there is no continuity, replace
the Cord Reel Assy, Body Parti-
tion Assy, or Cord Reel Partition
Unit.
• If there is a problem, replace the
Motor Set.
* Also check and replace
the ON/OFF Switch (with
the Fuse Unit).
• If there is a problem, replace the
Power Control Unit.
• Replace the ON/OFF Switch
(with the Fuse Unit/Thermo Pro-
tector).
*If a burn in the Motor
caused the Fuse to blow,
then also replace the
Motor.
• Replace the Power Control Unit.
• Replace the P.C.B A UNIT.