Toshiba MMW-UP0271LQ-E Service Manual page 69

Check code Check code name
Water temperature decrease
trouble
[A02]
(M-HWM)
Is the water
heater connected ?
YES
Is the water
heater normal ?
YES
Is the water heater
capacity selection correct ?
YES
Are characteristics
of TWI (TA) and
TWO (TC2) sensor
resistance normal ?
YES
Water heater trouble
M-HWM I/F P.C. board trouble
TWI (TA) sensor trouble
TWO (TC2) sensor trouble
NO
Are characteristics of
NO
TWI (TA) and TWO (TC2)
sensor resistance normal ?
NO
NO
– 69 –
Cause
NO
YES
Check setting of DN
code 61
Heater connection: 1
No heater connection: 0
Check and correct
Replace M-HWM I/F P.C.
board.
Select the correct
Replace TWI (TA) or
TWO (TC2) sensor.
Replace M-HWM
I/F P.C. board.
Check M-HWM
ambient
temperature.
Out of use range →
remove M-HWM