Samsung DTB-D700F Service Manual page 25

Troubleshooting
4-2
No locking
Check Vcc of
U2 (Tuner)
R5, L1
Yes
Check Vcc of
U2(Tuner)
L2
Yes
Check I2C of
U2 (29, 30)
R130, R131
Yes
Check serial
data &control
(R10, R11, R12, R13)
Yes
Check U101.
No
Check SMPS.
No
Check U1 Regulator.
No
Check, U101 Voltage.
No
Check U2.
Samsung Electronics