Au242Fhbha Troubleshooting; Communication Failure Between Indoor And Outdoor Units - Haier H-MRV Series Service Manual

AU242FHBHA troubleshooting:

1.Communication failure between indoor and outdoor units

Wired controller: E9; 4 flashes of TIMER lamp
Are communication terminals of
indoor and outdoor units
securely connected?
Are communication resistance and
capacitor of indoor PCB correct? See
NOTE
Check outdoor mainboard
0010450351. Make necessary
replacement
NOTE: 1. R49.R50 resistor in AS072-182FCBHA circuit and R40.R41resistor in AE072-242FCBKA
circuit have a resistance of 100 K instead of 47K. AS models and C28~C30 of AE models use 104
polyester resistors.
Is indoor unit address
properly set? Without
repetition?
yes
yes
Is shielded wire
used for
communication?
yes
Are communication wire
and power cable set
separately?
yes
Is there external signal
interference?
no
Is indoor mainboard poorly
welded?
no
yes
>a__WcU[S^ <[c >a`V[e[a`Wc
no
Reset address
no
Reconnect
Use shielded wire. Shield layer
no
should be grounded at single
point
no
wiring Separately
yes
Eliminate interference
yes
Replace indoor PCB
no
Replace indoor PCB
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