KX-PRX120UAW, KX-PRXA10RUW - Panasonic Telephone Service Manual (repair manual)

 ORDER NO. KM41401785CE

Premium Design Phone with 
Touchscreen

W: White Version
(for Ukraine)
(for Armenia)
(for Moldova)
(for Azerbaijan)
(for Kazakhstan)
(for Tajikistan)
(for Uzbekistan)
(for Turkmenistan)
(for Kyrgyzstan)
(for Georgia)

KX-PRXA10

(Charger Unit) 

(Handset) 

   Model No 

Base Unit    Handset       Charger Unit     Expandable 

KX-PRX120 

1 

  1 (PRXA10)             1              Up to 6  

KX-PRXA10 

 

  1 (PRXA10)         1 

  

 

(Base Unit) 

2

PAGE

PAGE

1 Safety Precautions -----------------------------------------------4

1.1. For Service Technicians ----------------------------------4

2 Warning --------------------------------------------------------------4

2.1. Battery Caution ---------------------------------------------4
2.2. About Lead Free Solder (Pbf: Pb free) ---------------4

2.2.1. Suggested PbF Solder -------------------------------5

2.3. Discarding of P.C. Board ---------------------------------5

3 Specifications ------------------------------------------------------6
4 Technical Descriptions------------------------------------------7

4.1. Block Diagram (Base Unit) ------------------------------7
4.2. Circuit Operation (Base Unit) ---------------------------8

4.2.1. Outline----------------------------------------------------8
4.2.2. Power Supply Circuit ---------------------------------9
4.2.3. Telephone Line Interface -------------------------- 10
4.2.4. Transmitter/Receiver ------------------------------- 10

4.3. Block Diagram (Handset) ------------------------------ 11

4.3.1. KX-PRXA10------------------------------------------- 11

4.4. Circuit Operation (Charger Unit) --------------------- 13

4.4.1. Power Supply Circuit ------------------------------- 13

4.5. Signal Route----------------------------------------------- 14

5 Location of Controls and Components------------------ 16
6 Installation Instructions--------------------------------------- 16
7 Operating Instructions ---------------------------------------- 16

7.1. For Service Hint ------------------------------------------ 16

8 Service Mode ----------------------------------------------------- 17

8.1. Engineering Mode---------------------------------------- 17

8.1.1. Base Unit ---------------------------------------------- 17
8.1.2. Handset ------------------------------------------------ 18

8.2. EEPROM LAYOUT (Handset) ------------------------ 19

8.3. Copying User Data when Repairing ---------------- 19

8.3.1. Phonebook ------------------------------------------- 19
8.3.2. Other User Data ------------------------------------- 19

8.4. How to Clear User Setting----------------------------- 20

8.4.1. Resetting both base unit and handset --------- 20
8.4.2. Resetting only handset ---------------------------- 21

9 Troubleshooting Guide --------------------------------------- 22

9.1. Troubleshooting Flowchart ---------------------------- 22

9.1.1. Check Power----------------------------------------- 24
9.1.2. Check DECT Link----------------------------------- 26
9.1.3. Check Touch Panel--------------------------------- 28
9.1.4. Check DECT RF part ------------------------------ 29
9.1.5. Check Handset Transmission-------------------- 30
9.1.6. Check Handset Reception------------------------ 31
9.1.7. Check TAM Operation Part ----------------------- 33
9.1.8. Check SD Card Part ------------------------------- 34
9.1.9. Check Camera Part -------------------------------- 34

9.1.10. Check Sensor Part --------------------------------- 35

9.1.11. Check WiFi, BT Part ------------------------------- 35

9.1.12. Check Battery Charge ----------------------------- 35

9.2. Troubleshooting by Symptom (Base Unit 

and Charger Unit)---------------------------------------- 36

9.2.1. Check Point (Base Unit)--------------------------- 36
9.2.2. Check Point (Charger Unit)----------------------- 38

9.3. Troubleshooting by Symptom (Handset) ---------- 39
9.4. Function Check at Factory Mode -------------------- 40

10 Disassembly and Assembly Instructions -------------- 43

10.1. Disassembly Instructions ------------------------------ 43

10.1.1. Base Unit---------------------------------------------- 43

This service information is designed for experienced repair technicians only and is not designed for use by the general 
public. It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting 
to service a product. Products powered by electricity should be serviced or repaired only by experienced professional 
technicians. Any attempt to service or repair the product or products dealt with in this service information by anyone 
else could result in serious injury or death.

There are special components used in this equipment which are important for safety. These parts are marked by 
in the Schematic Diagrams, Circuit Board Diagrams, Exploded Views and Replacement Parts List. It is essential that 
these critical parts should be replaced with manufacturer's specified parts to prevent shock, fire or other hazards.
Do not modify the original design without permission of manufacturer.

If lead free solder was used in the manufacture of this product, the printed circuit boards will be marked PbF.
Standard leaded, (Pb), solder can be used as usual on boards without the PbF mark.
When this mark does appear, please read and follow the special instructions described in this manual on the 
use of PbF and how it might be permissible to use Pb solder during service and repair work.

L When you note the serial number, write down all 11 digits. The serial number may be found on the bottom of the unit. 
L The illustrations in this Service Manual may vary slightly from the actual product.

3

10.1.2. Handset ------------------------------------------------44
10.1.3. Charger Unit ------------------------------------------45

11 Measurements and Adjustments---------------------------46

11.1. Equipment Required -------------------------------------46
11.2. The Setting Method of JIG (Base Unit) -------------46

11.2.1. Connections -------------------------------------------46
11.2.2. How to install Batch file into P.C.-----------------47
11.2.3. Commands --------------------------------------------47

11.3. Adjustment Standard (Base Unit)---------------------48

11.3.1. Bottom View-------------------------------------------48

11.4. Adjustment Standard (Charger Unit)-----------------49

11.4.1. Bottom View-------------------------------------------49

11.5. Things to Do after Replacing IC or X'tal ------------50

11.5.1. How to download the data -------------------------50

11.6. RF Specification-------------------------------------------51

11.6.1. Base Unit ----------------------------------------------51

11.7. DECT Frequency Table (MHz) ------------------------51
11.8. Bluetooth Frequency Table-----------------------------52

12 Miscellaneous ----------------------------------------------------53

12.1. How to Replace the Flat Package IC ----------------53

12.1.1. Preparation --------------------------------------------53
12.1.2. How to Remove the IC -----------------------------53
12.1.3. How to Install the IC---------------------------------54
12.1.4. How to Remove a Solder Bridge-----------------54

12.2. How to Replace the Shield Case ---------------------55

12.2.1. Preparation --------------------------------------------55
12.2.2. Caution -------------------------------------------------55
12.2.3. How to Remove the Shield Case ----------------55
12.2.4. How to Install the Shield Case -------------------56

12.3. Terminal Guide of the ICs, Transistors and

Diodes -------------------------------------------------------57

12.3.1. Base Unit ----------------------------------------------57

13 Schematic Diagram ---------------------------------------------58

13.1. For Schematic Diagram---------------------------------58

13.1.1. Base Unit (Schematic Diagram 

(Base Unit)) -------------------------------------------58

13.1.2. Handset (Schematic Diagram (Handset)) -----58
13.1.3. Charger Unit 

(Schematic Diagram (Charger Unit)) -----------58

13.2. Schematic Diagram (Base Unit) ----------------------59
13.3. Schematic Diagram (Handset) ------------------------61

13.3.1. KX-PRXA10RU---------------------------------------61

13.4. Schematic Diagram (Charger Unit) ------------------77

14 Printed Circuit Board-------------------------------------------78

14.1. Circuit Board (Base Unit_Main) -----------------------78

14.1.1. Component View-------------------------------------78
14.1.2. Bottom View-------------------------------------------79

14.2. Circuit Board (Handset) ---------------------------------80

14.2.1. KX-PRXA10 -------------------------------------------80

14.3. Circuit Board (Charger Unit) ---------------------------82

14.3.1. Component View-------------------------------------82

15 Exploded View and Replacement Parts List -----------83

15.1. Cabinet and Electrical Parts (Base Unit) -----------83
15.2. Cabinet and Electrical Parts (Handset) -------------84
15.3. Cabinet and Electrical Parts (Charger Unit) -------85
15.4. Accessories ------------------------------------------------86
15.5. Replacement Part List-----------------------------------87

15.5.1. Base Unit ----------------------------------------------87
15.5.2. Handset ------------------------------------------------88
15.5.3. Charger Unit ------------------------------------------89
15.5.4. Accessories -------------------------------------------89

15.5.5. Screws ------------------------------------------------- 89
15.5.6. Fixtures and Tools----------------------------------- 89

4

• Repair service shall be provided in accordance with repair technology information such as service manual so as to 

prevent fires, injury or electric shock, which can be caused by improper repair work.

1. When repair services are provided, neither the products nor their parts or members shall be remodeled. 
2. If a lead wire assembly is supplied as a repair part, the lead wire assembly shall be replaced.
3. FASTON terminals shall be plugged straight in and unplugged straight out.

• ICs and LSIs are vulnerable to static electricity.

1. Cover plastic parts boxes with aluminum foil.
2. Ground the soldering irons.
3. Use a conductive mat on worktable.
4. Do not grasp IC or LSI pins with bare fingers.

1. Danger of explosion if battery is incorrectly replaced.
2. Replace only with the same or equivalent type recommended by the manufacturer.
3. Dispose of used batteries according to the manufacture’s Instructions.

In the information below, Pb, the symbol for lead in the periodic table of elements, will refer to standard solder or solder that 
contains lead.
We will use PbF solder when discussing the lead free solder used in our manufacturing process which is made from Tin (Sn), 
Silver (Ag), and Copper (Cu).
This model, and others like it, manufactured using lead free solder will have PbF stamped on the PCB. For service and repair 
work we suggest using the same type of solder.

• PbF solder has a melting point that is 50 

F ~ 70 F (30 C ~ 40 C) higher than Pb solder. Please use a soldering iron with 

temperature control and adjust it to 700 

F ± 20 F (370 C ± 10 C). 

• Exercise care while using higher temperature soldering irons.: 

Do not heat the PCB for too long time in order to prevent solder splash or damage to the PCB.

• PbF solder will tend to splash if it is heated much higher than its melting point, approximately 1100 

F (600 C).

• When applying PbF solder to double layered boards, please check the component side for excess which may flow onto the 

opposite side (See the figure below).

Component

Component 
pin

solder

Remove all of the
excess solder