Aiwa BBHTN180 Service Manual page 49

5）TV failure
Fix the RF
set
Check if there
is I2C signal
at PIN4 &
PIN5 of TUNER1
N
Check the I2C
circuit
between
U8and
U2
TV no channel
Check if there is RF
N
signal input
Check if there is
+5V at PIN6 of
Check if there is
intermediate
frequency signal
Y
output at PIN12 of
Check the
tuner
- 48 -
Y
N
U2
Y
Y
U2
Check the signal
circuit between
U8 and
Service Manual
Model No.:
Check the power
supply circuit to
this PIN
U2
6