User Guide

After Sales
Technical Documentation
THA–4S
Troubleshooting Guide
Page 6
Original, 12/95
Logic Fault
Logic fault
Power drops off, does
Check clock
Y
N
Check the following:
If OK change N101
not assume local mode
signal of D100/
pin 7 4.85Vpp
4.8MHz
Check
VL1 N101/pin 20
VL2 N101/pin 3
4.85 V
–Soldering of N101
–Vbat N101/pin 1
–DETIN N101/pin 12>1.23V
Check the following:
If OK change B102
–Soldering of B102
–DC voltage of B102
–Soldering of D101
N
Y
is XRES 0V in
N101/pin 8
Check
MCU clock
D101/pin 69
4.85Vpp/4.8MHz
Check the following:
If OK change D101
–Soldering of X101
–D101/VL1, Vref, GND
–MBUS circuit V121
Y
N