KX-TU301RUME - Panasonic Telephone Service Manual (repair manual)

ORDER NO. KM41111515CE

Easy Use Mobile Phone

M: Metic Gray Version
(for Russia, Kazakhstan and Ukraine)

KX-TU301RUME

(Charger Unit)

(Handset)

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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.

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

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

4.1. Block Diagram (Handset)-------------------------------- 7
4.2. Circuit Operation (Handset)----------------------------- 8
4.3. Circuit Operation (Charger Unit) ----------------------10
4.4. Signal Route -----------------------------------------------11

5 Location of Controls and Components ------------------12
6 Installation Instructions ---------------------------------------12
7 Operating Instructions-----------------------------------------12

7.1. For Service Hint-------------------------------------------12

8 Troubleshooting Guide ----------------------------------------13

8.1. Troubleshooting Flowchart -----------------------------13
8.2. Troubleshooting by Symptom (Handset and

Charger Unit) ----------------------------------------------20

9 Disassembly and Assembly Instructions ---------------23

9.1. Disassembly Instructions -------------------------------24
9.2. How to Replace the Handset LCD -------------------26

10 Measurements and Adjustments---------------------------27

10.1. Handset Reference Drawing---------------------------27
10.2. Charger Handset Reference Drawing---------------28
10.3. RF Specification-------------------------------------------29
10.4. How to Check the Handset Speaker or

Receiver ----------------------------------------------------30

11 Miscellaneous ----------------------------------------------------31

11.1. Terminal Guide of the ICs, Transistors and

Diodes -------------------------------------------------------31

12 Schematic Diagram ---------------------------------------------33

12.1. For Schematic Diagram---------------------------------33
12.2. Schematic Diagram (Handset) ------------------------34
12.3. Schematic Diagram (Charger Unit) ------------------36

13 Printed Circuit Board-------------------------------------------37

13.1. Circuit Board (Handset) ---------------------------------37
13.2. Circuit Board (Charger Unit) ---------------------------39

14 Exploded View and Replacement Parts List -----------41

14.1. Cabinet and Electrical Parts (Handset) -------------41
14.2. Cabinet and Electric Parts (Charger Unit)----------42
14.3. Accessories ------------------------------------------------43
14.4. Replacement Part List-----------------------------------44

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• Repair service shall be provided in accordance with repair technology information such as technical guides 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