Kenwood NX-5900 Service Manual page 78

*1 If 12M, 18M or 33M has still abnormal voltage after the implementation of each procedure above, 54M(IC8), 12M(A1), 18M(IC11),
33M(IC5) or one of these peripheral circuit is broken.
54M (normally 5.4V at L12) has an abnormal voltage, check the MSP430G25KGCA (IC2) according to the following procedure.
Checking the operation of the IC2
Check that the voltage of VN of 54M (IC8-2pin)
is 13.6V.
Standard Voltage/Operating Voltage range
13.6V/13.6±15%
When VIN of 54M
is 13.6V.
Check that the signal BAT_CNT
of IC2-7pin outputs High (3.1V).
When the voltage of
BAT_CNT is not High.
Check that the voltage of DVCC of IC2-1pin is 3.1V.
When the voltage of
DVCC of IC2 is 3.1V.
Check that the analog voltage
of /BINT (IC2-5pin) is normal. (typically 2.6V.
Operating voltage range is 1.6V
*2 Checking the operation of the IC2 (/RST)
When the signal /RST (IC2-14pin) has an
abnomal output, check that the analog voltage of
/RST (IC2-6pin) is normal. (typically 2.7V.
Minimum detection voltage is 2.0V.).
Checking the operation of the IC2 (/BINT)
When the signal/BINT (IC2-13pin) has an
abnormal outputs, check that the signal /RST (IC2
-14pin) has correct output.
Checking the operation of the IC2 (/OVRB_OUT)
When the signal/OVRB_OUT has an abnormal
outputs, check that the /OVRB (IC2-2pin) is
High (3.1V) in the deck powered on.
1-78 (No.RA032<Rev.001>)
When VIN of 54M
is 0V.
When VIN of 54M is
out of operating
voltage range.
When the voltage of
BAT_CNT is not High.
When the voltage DVCC
of IC2 is 3.1V.
When a normal
value is confirmed.
3.0V).
When the voltage out-of-
range condition is confirmed.
When the analog voltage of
/RST(IC2-6pin) is normal.
When the analog voltage of
/RST (IC2-6pin) is below
2.0V.
When a normal
value is confirmed.
When a abnormal
value is confirmed.
When a normal
value is confirmed.
Check the voltage (13.6V [operating voltage range]) at both ends
of F1 (fuse). If F1 is broken, replace the F1 with a new one.
If F1 is not broken, 54M (IC8) or its peripheral cricuit is broken.
Set the supply voltage within the operating
voltage range. If set correctly, 54M (IC8) or its
peripheral circuit is broken.
54M (IC8) or its peripheral circuit is broken.
IC2, 31BU, 50BU or one of these peripheral circuit
is broken.
IC2 is broken.
Set the supply voltage within the operating
voltage range. If set correctly, IC2 or its
peripheral circuit is broken.
IC2 is broken.
IC2, 54M (IC8) or its peripheral circuit of is broken.
IC2 or its peripheral circuit of is broken.
IC2 or its peripheral circuit is broken.
IC2 is broken.