Yet Another Single Diode Failure Found In HAIER LED TV
This Haier LED TV model LE22B600 belonged to the hospital I work and was brought to me in a dead condition. I opened and cleaned the inside before looking for the trouble maker. The following picture is taken before cleaning up:
Fuse was intact. Could not find any burnt components in primary and secondary. ESRs of caps were ok. When I powered the TV and checked the output voltage, it was found dropped. That meant the primary switching was ok and something had gone wrong in the secondary. As I found two diodes connected in parallel in the secondary section and was sure that one of them might have got shorted, I checked and found it to be true. Removed both the diodes and checked it again.
One was ok, but one was short! Following pictures are the shorted diode checked in forward and reverse condition:
I replaced both the diodes and applied power and was glad to see the TV working:
Applied signal and found a crystal clear picture on the screen.
After allowing it to run for a couple of hours, fixed the back cover and run it again for a few hours:
As the on screen menu was in an unknown language, I took my techie friend’s help to change it to English:
Mission accomplished and satisfaction got added to its collection.
This article was prepared for you by Parasuraman Subramanian from India. He is 72 years old and has more than 30 years’ experience in handling antique equipment like Valve Radio, Amps, Reel Tape Recorders and currently studying latest tech-classes conducted by Kerala State Electronics Technicians’ Association. He has done graduation in BBA degree, private diploma in Radio Engineering and retired as MD of a USA company. Presently working as Consultant to Hospital and other institutions.
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Albert van Bemmelen
April 16, 2022 at 7:26 pm
Quick and professional repair as always!
Parasuraman Subramanian
April 16, 2022 at 8:40 pm
Many thanks!
Luis
April 18, 2022 at 3:14 pm
Lo agradezco pero es una falla
Fácil
Para los que vivimos en méxico y realmente reparamos equipos muy dañados con fallas casi imposibles de reparar me gustaría saber cómo repara usted un plasma es decir como rentinta las membranas de alto voltaje cuando se abren ambas ?
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I appreciate it but it's a bug
Easy
For those of us who live in Mexico and really repair very damaged equipment with faults that are almost impossible to repair, I would like to know how you repair a plasma, that is, how do you re-ink the high voltage membranes when both are open?
Parasuraman Subramanian
April 18, 2022 at 11:29 pm
Many thanks! I have not yet repaired a plasma TV. So, sorry! I am unable to follow the problems!
Bobby
April 16, 2022 at 7:57 pm
Thank you Parasuraman for sharing your idea.
Parasuraman Subramanian
April 16, 2022 at 11:11 pm
Many thanks!
Imoudu. O
April 16, 2022 at 10:34 pm
Good!! Thanks for sharing
Parasuraman Subramanian
April 17, 2022 at 9:14 pm
Many thanks!
Robert Calk Jr.
April 17, 2022 at 11:15 am
Good job, Parasuraman. Using your VOM to check the diodes is the best way.
Parasuraman Subramanian
April 17, 2022 at 9:14 pm
Many thanks!
ANIL KUMAR V K
April 17, 2022 at 9:49 pm
Excellent work sir
Parasuraman Subramanian
April 18, 2022 at 11:30 pm
Many thanks!
Waleed Rishmawi
April 18, 2022 at 3:48 pm
I have came across such fault many many times and it seems like diode is the main problem in these TV's. sometime find a bad mosfets in the back of the power board but mostely diodes. thanks man for sharing and be blessed today
Parasuraman Subramanian
April 18, 2022 at 11:31 pm
Many thanks for your comments!
Yogesh Panchal
April 20, 2022 at 12:11 am
Good Fix! Sir,
Parasuraman Subramanian
April 21, 2022 at 10:38 pm
Many thanks!