Panasonic KX-TG2853BXS

40
KX-TG2853BXS/KX-TG2854BXS/KX-TGA280BXS
10.2. Troubleshooting by Symptom (Base Unit )
If your unit has below symptoms, follow the instructions in remedy column.
Note:
(*1) Refer to Check Point (Base Unit) (P.40)
10.2.1. Check Point (Base Unit)
Please follow the items below when BBIC or FLASH is replaced.
Note:
After the measuring, suck up the solder of TP.
*: PC Setting (P.48) is required beforehand.
The connections of simulator equipments are as shown in Base Unit Reference Drawing (P.53).
Items Check
Point
Procedure Check or
Replace Parts
(A) 3.45 V Supply Confirma-
tion
VDD3 1. Confirm that the voltage between test point VDD3 and GND is 3.45 V ± 0.2 V. IC301, C301,
C303, R302,
R303, C310,
C311
(B) 3.0 V Supply Confirma-
tion
VDD2 1. Confirm that the voltage between test point VDD2 and GND is 3.0 V ± 0.2 V. Q2, R333,
R334, C332,
C333
(C) 1.8 V Supply Confirma-
tion
VDD1 1. Confirm that the voltage between test point VDD1 and GND is 1.8 V ± 0.1 V. Q3, C321, R325
(D) BBIC Clock Adjustment CLK 1. Input Command “conttx”, then you can confirm the current frequency of CLK.
2. Adjust the frequency of CLK executing the command “setfreq xx (where xx is
the value)” so that the reading of the frequency counter is 10.368000 MHz ±
10 Hz.
IC1, X1, R40,
C44, C45
(E) DTMF Generator Check - 1. Connect CN101 (Telephone Socket) to DTMF tester. (Road=600 Ω)
2. Link Handset and push dial key.
3. Confirm DTMF character.
4. Confirm that the high Group is -7dBm ± 3dBm.
5. Confirm that the low Group is -9dBm ± 3dBm.
D103, Q104,
R172, C174, R9,
IC1
(F)* Audio Check - 1. Link with Handset.
2. Input -45dBm/1kHz to MIC of Handset.
Measure the Level at Line I/F and distortion level.
3. Confirm that the level is -8 dBm ± 4 dBm and that the distortion level is < 5%
at TEL Line (600 Ω Load).
4. Input -20 dBm/1 kHz to Line I/F.
Measure the level at Receiver of Handset and distortion level
(*Receive volume set to second position from minimum).
5. Confirm that the level is -21 dBm ± 4 dBm and that the distortion level is < 5%
at Receiver (Volume Middle, 150 Ω Load).
IC1, C191,
R193, R194,
C181, Q171,
Q104, D103,
R172, C174, R9
(G) Charging Check - 1. Connect Charge Contact 12 Ω/2 W resistor between charge+ and charge-.
2. Measure and confirm voltage across the resistor is 2.7 V ± 0.3 V.
R304, R305,
R309, R310