Sam4s ER-280 SERIES, Service Manual

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SAM4S ER-280 SERIES 5-1
5 Troubleshooting
5-1 Power program
Power
Problem
Power Out
Ok? On Trans
Y
N
1. Check the Power Cable
2. Check the Power Transformer.
Power VDISP
(+30V) Ok?
Y
1. Check the Bridge Diode(BD2) on Main PBA
2. Check the VDISP signal whether it is short.
3. Check the Z-DIODE(ZD3), TR(Q14;2222)
4. Check the PFAIL Signal if it is OK
(PFAIL SIG controls VDISP on/off)
N
Power +24V
Ok?
Power VPRT
(+8V) Ok?
Y
1. Check the Fuse (FU1) on Main PBA
2. Check the Bridge Diode(BD1) on Main PBA
3. Check the Power S/W harness
4. Check the +24V whether it is short or open.
1. Check the KA34063(U16)
2. Check the TR KSA1010(Q15)
3. Check the VPRT whether it is short or open.
4. Check the VPH whether it is short or open.
N
Y
N
End
Power VCC
(+5V) Ok?
1. Check the KA34063(U22)
2. Check the TR KSA1010(Q16)
3. Check the VCC whether it is short or open.
Y
N
Power VDD
(+3.3V) Ok?
1. Check the LD1117(U26)
2. Check the VDD 3.3V whether it is short or open.
N
Y