Troubleshooting By Symptom (Base Unit ) - Panasonic KX-TG2853BXS Service Manual

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
(A) 3.45 V Supply Confirma-
tion
(B) 3.0 V Supply Confirma-
tion
(C) 1.8 V Supply Confirma-
tion
(D) BBIC Clock Adjustment
(E) DTMF Generator Check
(F)* Audio Check
(G) Charging Check
Check
Point
VDD3 1. Confirm that the voltage between test point VDD3 and GND is 3.45 V ± 0.2 V.
VDD2 1. Confirm that the voltage between test point VDD2 and GND is 3.0 V ± 0.2 V.
VDD1 1. Confirm that the voltage between test point VDD1 and GND is 1.8 V ± 0.1 V.
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.
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.
- 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).
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.
Procedure
40
Check or
Replace Parts
IC301, C301,
C303, R302,
R303, C310,
C311
Q2, R333,
R334, C332,
C333
Q3, C321, R325
IC1, X1, R40,
C44, C45
D103, Q104,
R172, C174, R9,
IC1
IC1, C191,
R193, R194,
C181, Q171,
Q104, D103,
R172, C174, R9
R304, R305,
R309, R310