Error Codes: System Malfunctions ESIE05-033–98 Part 3 – Troubleshooting313454.3 Malfunction of Transmission between Indoor Unit and Remote Controller (U5)Error code U5Error generation The error is generated when the microprocessor detects that the transmission between the indoor unitand the remote controller is not normal over a certain amount of time.Causes The possible causes are:P Malfunctioning remote controllerP Malfunctioning indoor PCBP Outside cause (noise...)P Connection of two master remote controllers (when using two remote controllers).TroubleshootingCaution Be sure to turn off power switch before connect or disconnect connector, or parts damage may beoccurred.Set one of the remotecontrollers to SUB, turn offthe power supplytemporarily, then restartoperation.Indoor unit PCBreplacement.Malfunction could beproduced by noise. Checkthe surrounding area andrestart operation.Change todouble-coreindependent cable.Control by 2 remotecontrollersAllindoor unitPCB microcomputernormal monitorsflashingUsingmulticoretransmission wiringbetween indoor unitand remotecontrollerFailure of remotecontroller PCB orreplacement of defectiveindoor unit PCB.Problem could be causedby external factor (noiseetc.) other thanmalfunction.Is "U5" displayedconstantly?SS1 of bothremote controllers isset to MAIN.Resetsnormally whenpower supply is turnedoff temporarily.YESYESYESYESYESYESNONONONONO
