Sometimes on your line of duty as a technician you may encounter a customer who brings to your shop equipment which maybe you don’t repair but insist that you check for them what could be wrong with their equipment.
Although I am not very experienced on mobile phone repair I usually get some customers who bring their phone to me for repair and usually if the problem is hardware related I undertake to repair it.
Mobile phone problem are frequently hardware related and if you are keen one can be able to make conclusions as to the faulty component even before opening the phone by listening to the customer complain.
Here is an example.
1. Customer complain:
When I place a call the phone does not indicate when the phone has gone through. Only hear the other party if the phone is set to loudspeaker.
Check the ear piece with analogue/digital meter set in low resistance range. Should be around 30 ohm when okay.
Solution: Usually changing the earpiece (speaker) cures this kind of a problem.
2. Customer complain:
I can’t hear the other person. In that case when the phone is dialed the phone rings and when you receive the call. You can’t hear the other person.
Solution: ear piece fault see above. Again one can use loudspeaker if the phone is equipped with one.
Nb: remember the ear piece could be okay but there could be other factors which could be hindering it from functioning. Be very keen to do observations around the ear piece, gasket, connector parts, the housing itself. - is it completely closed (home). Any loose bolts or missing bolts which could make the ear piece not to connect fully to the circuit board? Also check the orientation of the ear piece in connection to the main board.
Note: The earpiece and buzzer (ringer) are different. Some mobile phone has earpiece and loudspeaker- in this case the loudspeaker is used also as buzzer (Polyphonic Ring Tones)
3. Customer complain:
When I make a call the other person can’t hear me but I hear them
Solution: Check the microphone (mouth piece) is loose or faulty-usually replacing the mouthpiece cure this kind of problem.
4. Customer complain:
The phone goes off often, switch on and off after a small shake.
Cause: battery bad or shorted or battery connector loose.
Solution: change the battery/ Check the battery connector is firm.
Tip: Dust is one of the main killer of electronic gadgets and mobile phones is not excepted and therefore before you start suspecting component failure on mobile phone please be sure to do thorough cleaning of the PCB board with medicinal spirits and dry the board well with hair blower or hot air (this usually solve 30% of mobile phone problems)
That’s all for today guys
See you in our next class