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Service Manual STG5/7 intelligent STW5/7 intelligent form 9123999 rev. 05/2010
TROUBLESHOOTING
Description of part
Symptoms
Possible causes
Solving: checking/action
Drive motor
Motor does not run
Wiring.
Check the wiring.
Check the power to the motor.
Coil malfunction.
Check resistance of the coils.
Between whiteA and white wire
234Ω.
Between whiteA and brown wire
117Ω.
Between white and brown wire
117Ω.
Reduction gearbox. Check if reduction gearbox is
blocked.
Relay on power
board.
Check power on relay x14.
Motor runs after starting
it up by hand
Capacitor malfunc-
tion.
Check capacitor (see capacitor)
or connect new capacitor.
Motor stops during proc-
ess and comes in again
after a period of time
Coil overheated,
thermistor switches
off (105°C – 221°F).
Check position of fan blade. Air is
sucked up over the motor.
Check cooling circuit of motor.
Check if rotisserie is close to
another heat source.
Measure temperature motor during
process.
Fuse F1 or F2 burned
Short circuit in coil
to earth
Check insulation value of coil with
Megger on 500V. Minimum value is
0.5 MΩ.
Blower
Blower does not run
Wiring.
Check the wiring.
Check the power on the blower.
Coil malfunction.
Check resistance of the coils.
Between blue and brown wire
STG 7= 310Ω; STG 5= 310Ω.
Between blue and black wire
STG 7= 320Ω; STG 5=190Ω.
Between brown and black wire
STG 7= 630Ω; STG 5= 500Ω.
Relay on power
board.
Check power on relays.
Blower runs after starting
it up by hand
Capacitor malfunc-
tion.
Check capacitor (see capacitor), or
connect new capacitor.
Blower stops during proc-
ess and comes in again
after a period of time
Coil overheated,
thermistor switches
off (150°C – 302°F).
Check cooling circuit of blower.
Check if rotisserie is close to
another heat source.
Measure temperature blower
during process.
Temperature indication
on display runs up very
fast (180°C - 355°F after 5
minutes)
Blower does not
turn and heat stays
in top of cavity
Check the wiring.
Check the power on the blower.
Fuse F1 or F2 burned
Short circuit in coil
to earth
Check insulation value of coil with
a Megger on 500V. Minimum value
is 0.5 MΩ.