Hitachi RAC-25FPA, Service Manual, Page: 88 / 117

2.Failure phenomenon: The product will not receive a remote control signal.
[
Situation
]
The product does not receive a remote control signal. It is not very responsive.
(The product does run normally in response to the emergency operation switch.)
[ Estimated failure
locations ]
・ Remote control failure, remote control low battery level, remote control poorly set
・ Remote control light-receiving unit
・ Connector loose, wire break
・ Normal product (external factors: the remote control units for lighting equipment and other
equipment, electrical noise, etc.)
[
Cautions
]
[
Diagnosis flow
]
Initiating troubleshooting
・ Even if the product is trouble-free, a factor coming from outside the product may hamper the
reception of signals from the remote control unit.
・
Batteries may decline in capacity at low temperatures. Old batteries decline particularly much in
voltage in the morning and evening of winter, resulting in the poor arrival of remote control signals.
Instruct your users to use new alkaline batteries.
Does the remote control unit have a sufficient battery capacity?
If the liquid crystal display becomes
extremely faded when a remote control
signal is sent, replace the batteries.
No
Press the reset switch of the remote control unit,
then conduct another operation check.
Has the product worked?
Yes
Instruct your users to be sure to press
the reset switch after replacing the
batteries.
Yes
Did you identify a failure phenomenon?
Go on to "how to identify sources of
jamming in the reception of remote
control signals" (page
).
No
Yes
Conduct an operation check according to "checking the remote
control".
Is the remote control normal?
No
Yes
Replace the "remote control unit".
No
Is the CN13 securely connected?
Yes
Reconnect the connector correctly.
Yes
Replace the "display board".
Check for jamming due to an external factor while referring to
"how to identify sources of jamming in the reception of
remote control signals" (page ).
Is there jamming from outside?
Cope with jamming according to its cause.
No
No
[
Cautions in replacing the display board
]
Be sure to replace the indicating P.W.B. components.
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