Operation From The Indoor Remote Control Is Not Accepted, And A Check Code Is Displayed On The 7-Segment Display Of The Interface Pc Board Of The Header Unit; There Is No Display Of A Check Code On The 7-Segment Display On The Interface Pc Board Of; Remote Control - Toshiba MMY-MAP0724HT6UL Service Manual

8-5-2. Operation from the indoor remote control is not accepted,
and a check code is displayed on the 7-segment display of
the interface PC board of the header unit.
Header unit
Indoor remote
7-segment
control status
display
L08
E19 ⇔ -00
Alternate
blinking
No response
E19 ⇔ -02
Alternate
blinking
E20 ⇔ -01
Alternate
blinking
8-5-3. There is no display of a check code on the 7-segment
display on the interface PC board of the header unit,
although there is indoor unit that is not accepting operation
from the indoor remote control.
Header unit
Indoor remote
7-segment
control status
display
No response None
No display on the
indoor remote
None
control (no line is
output.)
Cause
Line addresses and indoor addresses of all the connected
indoor units are not set.
There is no header unit of group control.
Indoor unit power is not turned on.
Indoor/outdoor communication line is not correctly connected
to the U1/U2 terminal of the header unit ( Fig. 1). (Indoor/
outdoor cannot communicate before address setup.)
There is no of outdoor terminal resistance, or there
are two or more resistances (before address setup).
When connecting an indoor/outdoor communication line
between outdoor units under the condition of a connected
communication line between outdoor units ( Fig. 2).
SW08 setup error
Address setup is performed with connecting an indoor/
outdoor communication line between outdoor units ( Fig. 3).
Address setup is performed under the condition of
connecting multiple refrigerant lines ( Fig. 3).
Cause
The communication line is not connected between indoor
and outdoor (the unit that does not respond to the indoor

remote control).

Line address and indoor address are not set (the unit that
does not respond to the indoor remote control).
The power of the header unit of the group is not turned on in
indoor group control (the unit that does not respond to the
indoor remote control).
Group address is set to the follower unit for individual control
(the unit that does not respond to the indoor remote control).
The power is not turned on (the unit that is not displayed on
the indoor remote control).
The indoor remote control is not connected with a wire (the
unit that is not displayed on the indoor remote control).
Miswiring of the indoor remote control (the unit that is not
displayed on the indoor remote control)
Indoor remote control communication circuit error (the unit
that is not displayed on the indoor remote control)
If 460 V is incorrectly applied to the indoor remote control
terminal, the remote control communication circuit fails.
Set up addresses.
Set up a group address.
Turn on the power again. (In the order:
indoor ➝ outdoor)
Correct wiring
Check SW30 bit 2 of the header unit.
No connection between multiple refrigerant
lines: SW30 bit 2 is on.
Connection between multiple refrigerant
lines: SW30 bit 2 of the connected header
unit is turned on only for one line.
Correct wiring
Turn all SW08 switches to "off."
Correct wiring
Correct wiring
Modify the wiring.
Set up the address.
Turn on the power.
Set the group address to "0" in the case of
individual control.
Turn on the power.
Modify the wiring.
Modify the wiring.
Remove the fast-on terminal connected to
indoor remote control terminals A/B, and
check the voltage. If voltage is not applied
(normally 15 to 18 V), replace the PC board.
81
Countermeasures
Countermeasures