CHECKPOINT
Power cord
Fuse (Plug for UK only)
Main fuse (250V, 12 A)
Motor continuity
ON/OFF Switch
Thermal cut-out
Triac
Power board
* Rotary potentiometer
Hose or Suction inlet,
Tubes and nozzle
Dust bag / Central filter
Motor fan
* Rotary potentiometer
* Power board
* Rotary potentiometer
CONDITION
Motor fails to rotate.
(no noise is heard at all).
Motor runs but there is
no suction.
Noise or vibration
Motor does not change
power (runs always at
full speed)
Motor runs irregularly
METHOD OF INSPECTION
Check power cord continuity.
Check plug fuse continuity.
Check main fuse continuity.
Check motor continuity between
carbon brush holder tabs.
Check continuity across ON/OFF
switch tabs.
Check continuity across thermal
cut-out connection points.
(Assembled in motor)
Check if the triac is in open circuit.
(Assembled in PCB)
Check if the diac is in open circuit.
Check if the potentiometer is in
open circuit.
Check for any possible blockage in
the indicated parts .
Check if dust bag is full or central
filter is choked up.
Check dust accumulated in
motor fan.
Check possible bad contact of
power control potentiometer.
Check if power board circuit is
short-circuited.
Check possible bad contact of
power control potentiometer.
CAUSE / REMEDY
If there is no continuity, replace
the power cord.
If there is no continuity, replace
the fuse.
If there is no continuity, replace
the main fuse.
If there is no continuity, replace
the motor.
If there is no continuity, replace
the switch.
If there is no continuity, replace
the motor.
If it is in open circuit, replace
power board ass’y.
If it is in open circuit, replace
power board ass’y.
If it is in open circuit, replace
power control.
If there is any blockage, remove it.
If dust bag is full, replace with a
new one. If central filter is choked
up, remove and clean it out or
replace.
If there is dust accumulated in the
motor fan, replace the motor and
check filter condition (never try to
dismantle the motor fan)
If there is bad contact, replace the
power control.
If it is short-circuited, replace
power board ass’y.
If there is bad contact, replace
power control.
NOTE:
Parts marked with (*) only affect to model with power control.
4 TROUBLE SHOOTING GUIDE
7
MC-E7305 / MC-E7305K / MC-E7303 / MC-E7303K / MC-E7302 / MC-E7301 / MC-E7301K
