Kenwood NX-5700HB, Service Manual

Page: 63 / 106

(No.RA073<Rev.001>)1-63
Checking the output signal
from the MPU/DSP
Fail
Fail
Fail
Pass
Checking the control signal output from
the MPU/DSP
Points to be checked
Normal voltage
/FRST
D701(Anode side)
Points to be checked Normal voltage
SBC MPU/DSP side R51 3.3V
Remove R51 to check the voltage of the SBC.
if the MPU/DSP side is 0V,
the MPU/DSP or Flash Memory or mobile DDR
may be broken.
(1) /RST :MPU/DSP reset signal LOW Reset
(2) /BINT :Battery final voltage monitoring LOW Final voltage
(3) /OVRB_OUT :Battery overvoltage monitoring LOW Overvoltage
(4) /PSW_OUT :Power switch signal LOW ON
(5) /IGN_OUT :Ignition switch signal LOW ON
(6) /FRST :Flash Memory reset signal LOW Reset
(7) /CS_F :Flash Memory chip select signal LOW Active
(8) SBC :B control HIGH ON
(9) PRST :LCD reset signal LOW Reset
1.8V
If the /FRST is always 0V, the MPU/DSP
is broken.
Remove D701 to check the voltage of
Flash memory side R732.
If the voltage becomes abnormal, Flash
memory is broken.
Pass
Pass
Points to be checked Normal voltage
After power-on,
and
/CS_F IC704(4pin)
1.8V fixed later
If the IC704 (1pin) is 0V or 1.8V,
the MPU/DSP may be broken.
If the IC704 (2pin) is 0V or 1.8V,
the MPU/DSP or Flash memory may be
broken.
1.8V 0V 1.8V,
Descriptions of signal names