Panasonic KX-TG1283BXS, Service Manual

Page: 37 / 99

9 TROUBLESHOOTING BY SYMPTOM (HANDSET)
Ifyour unit has below symptoms, follow the instructions in remedy column. Remedies depend on whether you have DECT tester
(*1) or not.
Note:
(*1): A general repair is possible even if you don’t have the DECT tester because it is for confirming the levels, such as Acoustic
level in detail.
(*2): Refer to Check Point (Handset) (P.37)
9.1. Check Point (Handset)
Please follow the items below when BBIC or EEPROM is replaced.
Note:
After the measuring, suck up the solder of TP.
*: PC Setting (P.41) is required beforehand.
The connections ofadjustment equipments are as shown in Adjustment Standard (Handset) (P.43).
Items Check
Point
Procedure Check or
Replace Parts
( A )* 1.8V Supply Adjustment VDD1 1. Confirm that the voltage between test point VDD1 and GND is 1.8V ± 0.02V.
2. Execute the command “bandgap”, then check the current value.
3. Adjust the 1.8V voltage ofVDD1 executing command “bandgap XX“(XX is the
value).
IC1, Q2, C40
( B ) DC/DC Supply
Confirmation
VDD3 1. Confirm that the voltage between test point VDD3 and GND is 3.3V ± 0.3V
(Backlight is ON).
IC1, F1, C1,
C3, C57, R1,
Q1, D1, L1,57
( C ) 2.5V Supply
Confirmation
VDD2 1. Confirm that the voltage between test point VDD2 and GND is 2.5V ± 0.1V. IC1, Q3, C4,
C5
( D )* BBIC Confirmation - 1. BBIC Confirmation (Execute the command “getchk”).
2. Confirm the returned checksum value.
Connection ofchecksum value and program number is shown below.
IC1, X1,C7,
R19
( E )* EEP-ROM Confirmation - 1. EEP-ROM Confirmation (Execute the command “ChkTCA121XXrevYY”).
XX: country code
YY: revision number
2. Confirm the returned checksum value.
Note:
“XX”, “YY”, and “checksum” vary depending on the country version. You can
find them in the batch file, PQZZ- mentioned in
JIG and PC (P.41).
IC3, IC1, R39,
R40, R91,
R90, R96,
Q10, Q11,
C113
37
KX-TG1283BXS / KX-TG1283B XT / KX-TCA122CXS / KX-TCA122CXT / KX-TCA121CXS / KX-TCA121CXT