4-2 BRC-300/300PBRU-300/300PIs the AC adapterconnected, and isAC power (+12 V)supplied?Does +3.3 V existin pin 4 of IC1501on the SY board ?YesAre the fuses F1501to F1504 normal on theSY board ?One of the following isdefective.. DC IN jack. Harness between DCboard and SY board. DC boardCheck above in order fromthe top to identify thedefective part.NoYesSY board failure(IC1019 or the peripheralcircuit)Replace the defectiveparts or the SY board.NoSY board failure(IC1501 or the peripheralcircuit)Replace the defective partsor the SY board.YesConnect the AC adapter,and supply AC power.Check whether +12 V isoutput from the adapter’sDC IN jack. Replace theAC adapter if necessary.Does +12 V exist inpins 1 to 4 on theSY board ?YesNoNoIs the pin 107level of IC1019set to “H” on theSY board ?NoYesReplace the fuses F1501to F1504 on the SY board,and check the powersupply system.SY board failure(X1001 or the peripheralcircuit)Replace the defective partsor the SY board.Is the 25 MHzsignal input to pins96, 97 of IC1019on the SY board ?YesSY board failure(IC1502 or the peripheralcircuit)Replace the defective partsor the SY board.Noa-14-2. BRC-300/300P4-2-1. Troubles during Power-on Process of the Unita-1. The power indicator does not light and pan/tilt operations are disabled.
