Board Exchange Procedures; Replacement Of Indoor P.c. Boards - Toshiba MMU-UP0091HP-E Service Manual

10. P.C. BOARD EXCHANGE PROCEDURES
Indoor unit

10-1. Replacement of indoor P.C. boards

<Note: when replacing the P.C. board for indoor unit servicing>
The nonvolatile memory (hereafter called EEPROM, IC503) on the indoor unit P.C. board before replacement
includes the model specific type information and capacity codes as the factory-set value and the important
setting data which have been automatically or manually set when the indoor unit is installed, such as system/
indoor/group addresses, high ceiling select setting, etc.
When replacing the P.C. board for indoor unit servicing, follow the procedures below.
After replacement completes, confirm whether the settings are correct by checking the indoor unit No., Group
header unit/follower unit settings and perform the cooling cycle confirmation through the trial operation.
<Replacement procedures>
CASE 1
Before replacement, the indoor unit can be turned on and the setting data can be read out by
wired remote control operation.
Replacement of P.C. board for Indoor unit servicing and power on [2]
(for all indoor units connected to the remote control when the group operation control is performed.)
CASE 2
The EEPROM before replacement is incomplete and the setting data cannot be read out.
Replacement of P.C. board for Indoor unit servicing and power on [2]
Writing the setting data to EEPROM, such as high ceiling installation setting and optional connection setting,
(for all indoor units connected to the remote control hen the group operation control is performed.)
EEPROM data read out [1]
Writing the read out EEPROM data [3]
Power reset
etc., based on the customer information. [3]
Power reset
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