Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

I just don't get why the big caps originally got juice before I started troubleshooting and now nothing, even with the shorted rectifier. I wonder if the 2nd time the fuse blew(ordered some/popped one in/blew) if that caused some more issues. Damn, well I'll order one of these and go from there. Wish I could find a replacement board, my friend is bugging the hell out of me to get it back and I've only had it 6 days lol

[Agent24]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

Have a look through this, it should help you: http://www.repairfaq.org/sam/smpsfaq.htm

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

OK, so the rectifier is not in the circuit, the lamp did not light up, that means the TVS is OK which is connected between the AC pins of the rectifier. That is why I gave you the step on what to do track down the shorts. So the rectifier in place and the two FBs are lifted or still in place? Those two FBs, one is connected to the + out and one is connected to the - out. If the lamp does not light up with everything back in place, then what ever shorted out could have blown open circuits when the second fuse was put in.

FOLLOW-UP, I look at you pictures again (with big headache due to bad focused), the two ~pins of the rectifier are tied together and the it is set up as voltage doubler circuit, each main filter cap should have about 166Vdc at the two legs of each cap, the total voltage output is about 320VDC.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

Have a look through this, it should help you: http://www.repairfaq.org/sam/smpsfaq.htm

Thank you sir. Getting a better understanding of a few things.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

OK, so the rectifier is not in the circuit, the lamp did not light up, that means the TVS is OK which is connected between the AC pins of the rectifier. That is why I gave you the step on what to do track down the shorts. So the rectifier in place and the two FBs are lifted or still in place? Those two FBs, one is connected to the + out and one is connected to the - out. If the lamp does not light up with everything back in place, then what ever shorted out could have blown open circuits when the second fuse was put in.

FOLLOW-UP, I look at you pictures again (with big headache due to bad focused), the two ~pins of the rectifier are tied together and the it is set up as voltage doubler circuit, each main filter cap should have about 166Vdc at the two legs of each cap, the total voltage output is about 320VDC.

I just did the TVS and left the two FB's alone. Shall I go onto the next step and remove a leg on the FBs?

You're correct, ~ pins are tied together in the middle of the rectifier and when I checked the main filter caps with it still plugged in the AC, I didn't get any juice. I have capacitor/uf mode on my meter, is it worth removing them and checking that way or do you really need an ESR to check that?

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

Can you take the resistance reading of the TVS to see what resistance it has? do not solder it back in place yet.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

Looks like it's 000 out.

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

0 Ohms, K Ohms?, about the same reading if you short your meter probes together? If that is the case, that TVS did its job by crowbar the circuit. If you put that back in place, the lamp should light up.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

Yep, 0 k ohms and it's same reading when touching probes together. I'll give that a shot real quick and see if it lights up. If it does light up, should I move onto the next step you advised earlier in the pic? Edit: Nvm I re-read your pic post.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

Bulb still didn't light up. =/

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

That cannot be, if that TVS is shorted out, it is connected between Line and Neutral as you can see from the traces, that lamp should light up.
"0 k ohms" I would expect 0 Ohms without the K if the meter is in auto range.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

I don't know, I'm sorta confused. I lifted one leg and didn't get any light, soldered it back and same results. I looked again and the k went away, guess it was auto ranging. I've tried a 60w and 150w flood lamp.

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

With dead short, the lamp will light up, but for now just leave the TVS out for now and check the voltage where the B+ and the primary ground are, make sure to put other parts back in place. Lamp connections to the fuse holder are good?

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

Sorry but where is the B+ and primary ground you're talking about? I'll turn on the aoyue now, brb.

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

See post 31

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

It looks okay, bent out a little on one side from popping the fuse out but it looks okay.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

I'm getting 65.6 on the B+ and primary ground.

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

That is odd number, 65.6VDC? Just to be sure, measure a 1.5V battery to see what you get.

[budm]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

I just re-read your post 1.
"I get .53, .52 and then .98 This is a bad rectifier, correct?" That is not right, since there are 4 diodes in the bridge, it should show 4 readings of ~0.5. Then you are correct to say that it is bad, but you need to see 4 readings, not 3 readings.

[ALR]

Re: Toshiba 40RV525RZ-No Power/Standby-Power Supply Help!

I thought so too. First time I read it, it was in the 70's and then 60's and tried again and it's in the 50's. I got 1.48 on the battery