User Guide

Technical Documentation
NHB–3
PAMS
Troubleshooting
Original 26/97
Page 12
YES
FLASH programming
MBUS
registration
OK?
Display:
selftest failed
D231/MCU/pin 3; _RD
D230/ASIC/pin 97; RSTROBE
Power
stays on?
YES
YES
NO
Display:
selftest failed
NO
Short circuits in
data lines. Data line
disconnected, VREF
unconnected
MBUS line X100/5
+5 V after pwr on?
R166
+ 5 V?
VBATT
pins 5, 20?
Check X100
N271/pin 8/XRESET
+5 V after pwr on?
C113 OK?
R110 OK?
Change N271
MCU/D231/PIN67/RXD
+5 V after pwr on ?
NO
If D231 at
pin 66/TXD
doesn’t apply
+5 V change
D231
V160 base
∼1 V
Check
R165, R166
V161, R164
Check R163,
V160, R161,
R160, C160
Change first
D231
If R162 is OK
change D231
NO
NO
NO
Power supp. to the logic
circuits +5 V after pwr on?
Change N271
NO
NO
YES
YES
YES
NO
YES
YES
YES
NO
YES
YES
2
3
YES
NO
PIN46/TMR1
ASIC/D230/PIN67/MBUSDET