electronics, repairs, service manuals and datasheets discussion community for the repairs professionals and technicians
FAQSearchMembersGroupsRegisterProfilePM'sLogin/Out
KV27S15 power up problem - Q591, Q601, Q602, R607

 
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Equipment Repairs
View previous topic :: View next topic  
Author Message
dphoss
Guest





PostPosted: Sun Aug 06, 2006 1:20 pm    Post subject: KV27S15 power up problem - Q591, Q601, Q602, R607 Reply with quote

I have a Sony KV27S15 TV that went out - we were watching it and it just went out. I replaced the HOT (Q591), the two power switching transistors Q601 and Q602 and R607. All were bad. Measured the VDRs and they looked good ...at least as a static check.

After I put the new parts in (Q591, Q602, Q601, R607), I used a variac and slowly brought the AC up. The power relay kicked in (~40-60V AC) and I eventually got it up to 110 with only sound. I had it on for 40+ minutes with only sound while I was looking for why I didn't have video. I pushed on the heat sink for the power transistors and suddenly, the video came on. It was on for ~1-2 minutes and I heard this chirping and then the set went dead (Q601, Q602, Q591, R607 all got shorted out again...actually the resistor R607 opened up). Q591 CE is shorted and so is it on Q601 and Q602.

Any ideas on what might be the cause? I have another set of parts but I'm hesitant to put them in without knowing what else is wrong. Could it be the flyback or the horizontal drive transformer? How can I test the flyback or HDT?

Also, anyone have a service manual for the KV27S15? I've got the power section of the schematics and that's it.

Any help would be appreciated.

dap
Back to top
liu32310
Guest





PostPosted: Tue Dec 05, 2006 7:07 pm    Post subject: About Sony KV-27S15 power section of the schematics Reply with quote

Hello,

I have a some TV set and have the same problem with yours, and I found my two capacitors( C610,C612) were burned out. So Maybe your C610 and C612 also have problem. Hope that helps. I am looking for the parts set you used to fix my TV set currently. Could you tell me where you bought them? Thank you very much.


Jin Smile
Back to top
minnie



Joined: 18 Aug 2005
Posts: 2877
Location: Hell

PostPosted: Tue Dec 05, 2006 11:03 pm    Post subject: Reply with quote

You didn't fix the reason the hot, 601,2, r607 blaa blaa blaa fry. Solder up the horizontal drive transformer. If in doubt where it is solder up any transformer in the set.
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Equipment Repairs All times are GMT
Page 1 of 1

 
Jump to:  
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


Електроника София - Service Manuals Free Download - Prikachi - Service Diagrams

Free TV Schematics Download - HARDW.net - Pinout Master - Jabse Search - Jabse.InK  - Pulsator

Connector Pinout Forum - Новини - SnimkiOt.com - безплатен DNS - Whois разузнаване - Poblizo.com : пътешествия