Panasonic KX-TG4221N Service Manual page 36

KX-TG4221N/KX-TG4222N/KX-TG4223N/KX-TG313SK/KX-TG4224N/KX-TG4225N/KX-TGA421N
10.1.5.2. Handset
Does Handset make link with Base Unit?
(Correct working unit)
NO
Is the voltage of TP VBAT about 2.2~2.8 V?
YES
Is the voltage of TP 1.8V about 1.8 V?
YES
Is the voltage of 36 Pin (IC5) about 2.2~2.8 V?
YES
Does the RF clock (CLK) oscillate: 10.368 MHz
in Handset Test Mode?
YES
Check the RF part
Cross Reference:
Power Supply Circuit/Reset Circuit (P.21)
Check the RF part (P.37)
Note:
*1 How to adjust the frequency of X1:
To see the frequency, execute the command "SFR", then check the TP_CKM (IC5-52pin).
To adjust frequency, send command "SFR
Refer to Things to Do after Replacing IC or X'tal (P.54) for Handset.
YES
Handset is OK. Check Base Unit.
NO
Check the batteries.
NO
Check around Power Supply Circuit/Reset Circuit.
NO
NO Check around X1 and RF module and adjust
clock frequency.
" until the frequency counter becomes10.368 MHz±55HZ.
36
*1