View previous topic :: View next topic |
Author |
Message |
arabidopsis
Joined: 02 Jul 2011 Posts: 1 Location: Portugal
|
Posted: Sat Jul 02, 2011 7:27 pm Post subject: Nokia Mono Plus II - Dead with Stand-by LED flashing |
|
|
Hello!
I have a TV Nokia, chassis Mono Plus II for repair (first time I met this chassis).
It does not power up but makes a short hiss (apparently tries to start and shuts down immediately) and Stand-by LED remains flashing.
Voltage in the switching supply capacitor was only 175V and after replacing input rectifier diodes (all measured OK but one dropped 85V!), was corrected to the required 325V.
Except for the TEA2164, all significant components in the switching supply were measured or replaced.
However the voltage supply to pin 16 of TEA2164 remains at 3.4V (should be 10-14.5V) and voltage at pin 3 is 4V, when it should be <1V (overload protection?).
Any suggestion about what can be causing this?
If it's anywhere in the switching supply, it does not make much sense, as the microprocessor is driving the LED and, for that, needs power that is provided by the TEA2164 + BUF405.
Anyway, replacing the TEA2164 for testing or repair is not an option (at 40€ unit cost, better trash the TV).
I can't find repair tips for this fault anywhere and most replies I found in web forums are simply useless.
I just hope someone here knows this chassis and can shed some light on the origin of this fault.
Thanks in advance for any help.
Jose |
|
Back to top |
|
|
torbjorn
Joined: 07 Jun 2007 Posts: 370 Location: Sweden
|
Posted: Fri Jul 08, 2011 11:51 am Post subject: |
|
|
I have encountered the same symptom due to a faulty flyback transformer in a Nokia Euromono chassis. Try the classic troubleshooting method of disconnecting supply to the horizontal output, load the power supply with a 230 V 40 W bulb and check if the power supply then delivers correct voltages. Of course, it could be any other problem with the horizontal output too, not necessarily the transformer. |
|
Back to top |
|
|
|
|
|
You can post new topics in this forum You can reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
eServiceInfo on FB -
Service Manuals Free Download -
Service Diagrams
Free TV Schematics Download -
HARDW.net -
Pinout Master -
Jabse Service Manual Search -
Jabse.InK -
onTap.bg
SnimkiOt.com -
Poblizo.com : пътешествия
Latest Service Manuals :
INST64 NOKIA • aspire 8730 8730z 8530 acer • clevo d470v d480v sager np4780 Clevo • [radial thru-hole] UMH Series Samcon • dm130MVZ SCHM ALINCO • AZ3705 BA 1219895632 Philips • 6-5 Rolsen • t 590 DUCRETET THOMSON • Philips 22AC730 Philips • l2g 43 t Philips •
|