F8-Main External Control Panel And Module Panel Communication Error - Toyotomi KURO Mini Service Manual

（16）F8-main external control panel and module panel communication error
（exclusive of external machine of single panel）
Cause: Only the models with the module panels separated with the
main external control panels may have this error. When the machine is
running normally, the module panel and the main external control
panel would coordinate with each other on the communication to work
Explanation of
and when the communication is off, the main external control panel
would raise the alarm of "main control panel and module panel
error
communication error". Only "module panel, data line and main
external control panel" are related to such communication.
Inspection path: data line connection → module panel power
→module panel →main external control panel
Tools required
Multimeter and regular module panel.
for inspection
Frequent Module panel and main control data line, module panel and main
problematic part external control panel.
1. First check if the communication connection line (mostly 4 chips)
between the module panel and main contrl panel gets loose and if the
connection is faulted.
2. Measure and check with a multimeter if the power from the main
external control panel is normal and especially note that if the 5V
(3.3V) power is led to the module panel. Eleminate the possibility that
Inspection
it's not running normally because there is no 5V (3.3V) power at the
procedure and
module panel.
key points
3. The maintenance personnel shall replace the module panel of the
faulted air conditioner with a regular module panel taken with him and
if the communication error disappears when the external machine is
switched on, it means the original module panel is faulted and if the
error is still there, maybe the main external control panel shall be
replaced.
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