This CRT TV don’t start, only the red led blinks 11 times. The customer said that he uses to start the TV by pushing on/off on remote control 11 times, and the TV works fine. But Sometimes this doesn’t work and the TV stay on STB. The TV was repaired by another repairer without success.

Self-diagnostic

E11…8V
8V??????? What that means? IC 604 is faulty?
The IC604 deliver 8V and 5V, but when set is on, both tensions are correct and the control don’t occur to shut down the set. The 3.3v and 5Vstb are correct when the set works fine and when it is in protection mode.

Challenge

Why the set works when I push 11 times on/off on remote control? All capacitors around IC 601 (MCZ3001D) are good. I noticed that the 5V in PIN 7(ss) remains absent in protection state, but comes and drops immediately when I push the set on.
I changed the C608 (4.7µf) but no result. I conclude that the problem is in ss (soft start), the TV works immediately when I heat the ss PIN with my soldering iron.
I proceed as follow:
I tried this solutions on the surface mount components.
1- Change the value of C608 to 10µf, but still the same problem.
2- I increase the value to 33µf, still no change.
3- When I want to solder negative pin of a 22µf to GND I solder it to positive pin of C607 without paying attention. Then I switch on the set and it works fine. I try several times it works and that ends the problem.

I switch the set off without reassemble it to see what will happen the next day. Effectively the next day it works fine, when I proceed to reassemble and solder correctly the capacitor I remark that the (-) of capacitor C608 is wrongly solder to +C607.Thus I correct my error. My great surprise the set does not work and the flashing 11 times. I desolder again the C608 and resolder its negative to positif of C607, and the set works without fault.
C607 is for PIN timer and this accident correction doesn’t represent any danger for the set because OCP works and all tensions in IC are correct and secondary tensions correct too. I believe that the fault, which took 3 hours to resolve, was in the end fixed by accident.

Lessons Learnt

According to solutions given by repairers in the net we need to change a lot of components from FBT to secondary ic’s and diodes. There are many specific cases, be methodise when checking components. I suspected the SS since the beginning. My idea was to replace the IC601 if changing C608 value doesn’t work.

About

Bougrine-Professional Electronic Repairer From Morocco field:Dental Chairs & Stools , handpieces , micromotors etc.. dental supply equipments: Sterilizers,

3 comments on “CRT TV Fault Fixed By Accident

  1. Bougrine says:

    CRT TV Fault Fixed By Accident
    I apologize for this error:
    Self diagnostic:
    E8………..8V
    Correct is :
    E11……….8V

  2. Rolando Salgado says:

    Thanks for share your experiences, I have a question, with a good tester with capacitance meter for example fluke175 you can sure if a capacitor is in shortcircuit, open, or change value, for example to test the snuber capacitor in a tv, thanks. sorry for my bad english
    Rolando

  3. philip says:

    hi sir,
    my sony trinitron color tv kv-1982m7 has a voltage on the screen my problem is when i put the antenna there is no tv broadcaST no reaction just a black screen. On-screen display just a number of channels appears in color green. i tried the dvd but still no video when i tried to preset the channels but tuning has no reaction can you help me with this? thanks

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