User Guide

PAMS
Technical Documentation
NHD–4
Disassembly & Troubleshooting
Page 10
Original 11/97
Troubleshooting Diagram; Flash Programming, part 1
YES
FLASH programming OK
MBUS
registration
OK?
Does LCD
display turns
Check D706 pins 3,80
ASIC pins 130,86
Power
stays on?
YES
YES
NO
Does LCD
display turns
NO
Short circuits in data
data lines. data line
disconnected, VREF
disconnected
MBUS line X701
pin 5, Is 4.75V after
VBATT
N500 pin 5,20
Check X701
N500 pin 8/XRESET
3V after power ON?
C507 OK?
R500, R503
Change N500
D706 pin 67
+3V after power ON?
NO
Change D706
Check V703,
R728, R726,
NO
Power supp. to the logic
circuits +3V after power
Change N500
NO
NO
YES
YES
YES
NO
YES
YES
YES
NO
2
3
YES
ON?
OK?
NO
YES
pwr ON?
R727, if OK
change D706
ON?
ON?
Check that pin 4 of D500
is 4.75V. Also check the
control line, it should be
high (3V on Pin 1 of
D500).
?