Riddled TV Repair Forum
Service Menu and Manual Schematics
 
   
 FAQFAQ   SearchSearch   RegisterRegister 
   Log inLog in 
Olveia 542-B11 - no power up   Goto page 1, 2  Next  
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair
 
Author Message
desrosiers13



Joined: 01 Aug 2015
Posts: 6
Location: Michigan

PostPosted: Sat Aug 01, 2015 5:51 pm    Post subject: Olveia 542-B11 - no power up Reply with quote

I searched the forum extensively and no one seems to have my exact scenario. Many are close, but always a variable.

I have recently acquired an Olevia 542-B11. I plugged in the tv and on came the Olevia splash screen and then away it goes. It has a consistent blue led when the tv is powered off and it turns off when powered on. The screen just flickers that first time and then lights out.

Here is what I have researched and tried...
- Check all cable connectors for power output.
-My dad and I checked all the power being sent from the power supply and all are giving a perfect reading.
- Check all capacitors and replace them all.
- I checked every capacitor visually and with a meter and all read out perfectly.
- Check all transistors on both inverter boards.
- I checked every transistor to both Inverter Boards. Every transistor gives a perfect reading as well.

When I power on the tv with the back off, you can see the light turn on and off very quickly once. There are numerous red LEDs that stay on until I power off the TV. I can turn the power off the tv with either a remote or the button.

Im not sure about my next step. I have included photos for everything we tested.


click image upload


img host


upload pictures online


uploadimage

[/img]
Google

PostPost subject: Advertisement

JTS1957



Joined: 21 Jan 2009
Posts: 2224
Location: Far, Far Away

PostPosted: Sat Aug 01, 2015 7:11 pm    Post subject: Reply with quote

I need to know what is occurring to the voltage on the following points:
CNS1 O/F
CNS1 B-ON

CNS3/CNS4 B-ON

I need you to connect DVM meter to 'monitor' each point in turn. I do NOT want you to 'hold' either test lead in place. Tack solder a wire to each point and connect DVM leads via alligator or hook-type clips. I need to know the status of each point from the time you plug the TV in, hit the power button, Splash screen appears, Splash screen goes away. (example: voltage at CNS1 starts at zero, set is plugged in and voltage stays zero, power button is pressed to turn set on and voltage goes to 5VDC, it stays at 5VDC while splash screen shows and then goes to zero when the splash screen goes away.)(IF both B-ON test points exhibit the exact same voltage behavior, you only need to state it once.)
You may want to consider rechecking the rest of B-plus voltages in the same way.
desrosiers13



Joined: 01 Aug 2015
Posts: 6
Location: Michigan

PostPosted: Sat Aug 01, 2015 8:51 pm    Post subject: Reply with quote

I don't have a soldering iron. I can get one from my dad tomorrow and I'll start working on it. In the mean time, I'm going to recheck the inverter transistors.

Thank you for the quick reply.

Dave
desrosiers13



Joined: 01 Aug 2015
Posts: 6
Location: Michigan

PostPosted: Sat Aug 01, 2015 10:00 pm    Post subject: Reply with quote

OK, I was able to get the results. I posted the spreadsheet below. The number seemed to change each time the splash screen kicked in, so I took 3 readings per item. Hope this is what you were asking for.


image hosting 20mb
JTS1957



Joined: 21 Jan 2009
Posts: 2224
Location: Far, Far Away

PostPosted: Sun Aug 02, 2015 7:57 am    Post subject: Reply with quote

JTS1957 wrote:
I do NOT want you to 'hold' either test lead in place.


So you were doing EXACTLY what I told you NOT to? Try again. and what is Switch off / Switch on? Power strip instead of plug in/unplug? or is there a vacation switch?

In regards to other posts not being exact to your complaint: This ain't horseshoes, it's more like explosives, you usually only have to be close enough.

The capacitors that you 'replace them all,' were those ONLY on the power supply board or the WHOLE set? and did they include THESE and are pictures before or after changing them?
Google

PostPost subject: Advertisement

desrosiers13



Joined: 01 Aug 2015
Posts: 6
Location: Michigan

PostPosted: Sun Aug 02, 2015 9:06 am    Post subject: Reply with quote

Yes, a vacation switch. Sorry I meant to add that in.

I never replaced any of the capacitors. My dad and I measured them with a meter and all appeared to be working as supposed to.

I figured until I could get the soldering iron, maybe the measurements would show some sort of sign perhaps.

Also, that post you pointed me to I know was for a photo reference, but I read that post and the ailments were different than what my TV projects. Thats what I said none of the posts were the same. I get much further in the power on cycle than that individual did, so i assumed the fix would be different.
JTS1957



Joined: 21 Jan 2009
Posts: 2224
Location: Far, Far Away

PostPosted: Sun Aug 02, 2015 9:49 am    Post subject: Reply with quote

Post pointed to:
JTS1957 wrote:
NOT significant. Bulging/Physically Leaking/Value is not only defects a cap can have.
Did you replace all of the following (less than $10.00)?
CS21 1500ufd 16Volt, CS22 1000ufd 16Volt, CS28 100ufd 25Volt, CS18 100ufd 25Volt, CS23 680ufd 25Volt, CS8 680ufd 25Volt, CS19 1000ufd 35Volt, CS25 1000ufd 35Volt, CS7 1000ufd 35Volt & CS24 470ufd 35Volt.


Photo of PS. May just be angle, but the two black caps at center just left of double heat sinks appear domed.

desrosiers13 wrote:
Here is what I have researched and tried...
- Check all cable connectors for power output.
-My dad and I checked all the power being sent from the power supply and all are giving a perfect reading. 5Vs(standby/all time - as long as AC cord is plugged in) / 5V / 18V AND 24V? (and ALL FOUR only while set is turned ON).
- Check all capacitors and replace them all.
- I checked every capacitor visually and with a meter and all read out perfectly.
- Check all transistors on both inverter boards.

You can see why I asked. Which now brings up questions: CAPS: What was being checked? (value/ESR, etc.) / by what instrument? (brand/model) / under what conditions? (In circuit/Out of circuit, etc.).
Also for transistors: What was being checked? (IF they really are/were transistors - many WILL be FETs) by what instrument? (brand/model) / under what conditions? (In circuit/Out of circuit, etc.).
desrosiers13



Joined: 01 Aug 2015
Posts: 6
Location: Michigan

PostPosted: Sun Aug 02, 2015 3:23 pm    Post subject: Reply with quote

you are absolutely right. those are have a slight dome to them. i don't know how i missed that. i will go ahead and replace those.

my dad has a nicer meter than i do (I'm not sure of brand) but when he put the leads on the +/- of the caps, it was counting up and then he reversed and it would count down, as if charging and discharging. I don't know of all the terminology, I'm far from knowing about this.

we tested them by their posts and under the circuit board. we were able to get readings like this on all the capacitors.

here is a link to show you how I was testing the invert boards:
https://www.youtube.com/watch?v=b36w2GNrH6Y
JTS1957



Joined: 21 Jan 2009
Posts: 2224
Location: Far, Far Away

PostPosted: Sun Aug 02, 2015 4:34 pm    Post subject: Reply with quote

Comparing apples to oranges. Not even your brand, let alone same model.
Basically he's checking all those dual diodes (and transformer (xfmr) primaries and secondaries).
The following will work on all sets that use transformers. I just make comparative ohm readings of each xfmr winding. ALL primaries of the SAME part number xfmrs will give a numeric reading, all readings will be within a couple of percent. ALL secondaries will give a numeric reading (Quite a bit different than that of the primary), all readings will be within a couple percent. You don't really even need to know which is primary or which is secondary.
So pin 7 to pin 10 on your sets 4 xfmrs (for secondary), Primary is hard to see through SJ picture's plastic cover, carefully look at foils & actual pins to see if they are actually using a pin or not.
desrosiers13



Joined: 01 Aug 2015
Posts: 6
Location: Michigan

PostPosted: Sun Aug 02, 2015 8:07 pm    Post subject: Reply with quote

Im not sure what happened but I put some things back together and tried it again and the backlight stayed on. TV is working beautifully. Replacing the Caps was scheduled for Wednesday but all seems to be working fine now.

Who knows how long it will last, but its strange its functioning.

Thank you for all of your time for the replies and knowledge. Very much appreciated.
Display posts from previous:   
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair All times are GMT - 6 Hours
Goto page 1, 2  Next
Page 1 of 2

 


Disclaimer: All information provided by RiddledTV is strictly for information purposes only. Please observe all warnings displayed on your electronic
devices. This information should only be used to help diagnose work, and all service should be performed by a qualified technician.
Contact Us       Privacy Policy       Copyright © 2015 RiddledTV.com       Advertise on RiddedTV.com