Toshibia 40rv525u Green Blinking light and questions about Caps!!

[retiredcaps]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

10,11,12 5v+ --- 5.07
13 Pwr --- 2.6 pulse

Okay, 5V is good. This might be your standby voltage. Normally, the legend is marked as 5VSB or something like that.

Pin 13 is probably your power on signal from the main board. Normally it is > 3V, and if it is pulsing, then something isn't quite right.

I circled 3 voltage regulators on the main board.

1) List each part number.
2) Measure each pin (except the tab) with respect to ground.
3) Report all readings like the following.

U101 - AS1117-33
pin 1 - 0.0 V
pin 2 - 3.3 V
pin 3 - 5.0 V

If the voltage regulators check out, we need to check other things on the power board.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Okay, 5V is good. This might be your standby voltage. Normally, the legend is marked as 5VSB or something like that.

Pin 13 is probably your power on signal from the main board. Normally it is > 3V, and if it is pulsing, then something isn't quite right.

I circled 3 voltage regulators on the main board.

1) List each part number.
2) Measure each pin (except the tab) with respect to ground.
3) Report all readings like the following.

U101 - AS1117-33
pin 1 - 0.0 V
pin 2 - 3.3 V
pin 3 - 5.0 V

If the voltage regulators check out, we need to check other things on the power board.

Hmm, I don't see a picture, maybe something happened?
What do you mean (except the tab) are you Referring to the Tab on a Mosfet Like Device?

OK I could be wrong here but it seems like what is happening in that it turns on senses an overload and then shuts off. Like a Protection Circuit, Thats what it seems like to me anyway.

[retiredcaps]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

oops.

[retiredcaps]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

What do you mean (except the tab) are you Referring to the Tab on a Mosfet Like Device?

The tab is the top fat part. The 3 pins are below the tab.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

OK Here they are Also the Middle legs is not connected to the board. Pins numbers are from left to right when facing the Tab.

Legend U13
78m096
RA837

Pin #1 0.05
Pin #2 0.00
Pin #3 0.50 However, That is the Spike the Curent Jump Up for and then starts to drop off.

Legend U14
7805A
J8 1A

Pin #1 0.50 However, That is the Spike the Curent Jump Up for and then starts to drop off. This seems Identical to Pin #3 of U13
Pin #2 0.00
Pin #3 0.00

Legend U7
AIC
1084-33PM
877H8

Pin #1 0.00
Pin #2 Seeing a spike around 0.71 then start to drop back off, till it spikes again.
Pin #3 Same as Pin # 2 but a Higher Voltage 1.35 or So.

Also, note that I am not pressing the power button the tv the seems to power itself up then shuts down right after and this just repeats.

Should I try disconecting the inverter so there is not a load?

[tom66]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Yes, disconnect the inverter.

It looks as if the power supply is not starting up.

Causes include:
- bad output caps (rare - and this unit uses nice caps)
- bad startup cap (common even in good units)
- shorted diode
- shorted inverter (they usually have a fuse though)

Post a picture of the solder side (bottom) of power supply, we can have a look for shorted diode (in my experience the most common cause of this problem.)

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Yes, disconnect the inverter.

It looks as if the power supply is not starting up.

Causes include:
- bad output caps (rare - and this unit uses nice caps)
- bad startup cap (common even in good units)
- shorted diode
- shorted inverter (they usually have a fuse though)

Post a picture of the solder side (bottom) of power supply, we can have a look for shorted diode (in my experience the most common cause of this problem.)

Ok Thanks for the Help! I took the inverter off and the Same Thing Happened. Where are the Startup Caps located? On the Power Board or the Main/ Video?

I'll get a Pic in a Sec Just Want to Let soem of the Voltage Drain Before I go Stick My Hand in there.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Here are the Pictures I Took them next to a window thinking that It wouldn't create glare like the Flash but they still have it.

[tom66]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Looking at the layout of this power supply, it's clear that there is no startup cap for the main rails (as the primary of the main transformer has just one winding); the Vcc for the main controller (5V/12V/24V) is developed from the standby supply and as that is working, it's unlikely to be the problem.

Testing diodes:

Turn the TV off & wait 1 minute for the main bulk caps to discharge (these might carry 200V DC each, so can give a nasty shock!)

Flip the board upside down so you can see the solder side.

Get out your multimeter, and set it to the diode test mode. It looks like this: ->|-

If you do not have a diode test use the 2000 ohm / 2k ohm range - this is often the same or combined onto one range.

Initially, do not probe anything, and note the reading you get. It should be either " OL " or a single left-hand 1. This is your "open circuit" reading.

For each highlighted diode (red), test all six combinations of pins. Counting from the top: 1-2, 1-3, 2-1, 3-1, 2-3, 3-2. Typically, we are expecting around 120 - 800 from 1-2 and 2-3, and all of the other readings to report open circuit as above.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Looking at the layout of this power supply, it's clear that there is no startup cap for the main rails (as the primary of the main transformer has just one winding); the Vcc for the main controller (5V/12V/24V) is developed from the standby supply and as that is working, it's unlikely to be the problem.

Testing diodes:

Turn the TV off & wait 1 minute for the main bulk caps to discharge (these might carry 200V DC each, so can give a nasty shock!)

Flip the board upside down so you can see the solder side.

Get out your multimeter, and set it to the diode test mode. It looks like this: ->|-

If you do not have a diode test use the 2000 ohm / 2k ohm range - this is often the same or combined onto one range.

Initially, do not probe anything, and note the reading you get. It should be either " OL " or a single left-hand 1. This is your "open circuit" reading.

For each highlighted diode (red), test all six combinations of pins. Counting from the top: 1-2, 1-3, 2-1, 3-1, 2-3, 3-2. Typically, we are expecting around 120 - 800 from 1-2 and 2-3, and all of the other readings to report open circuit as above.

OK, I tested like this I think thats what you Meant from the top,
|1
2|__
| 3
I got these readings,

D203 Top in Picture,

1-2, ~1200 keeps climbing until out of range
1-3, 003 amusing open just something because its a semiconductor?
2-1, ~1200 keeps climbing until out of range
2-3, ~1200 keeps climbing until out of range
3-1, 002
3-2, ~1200 keeps climbing until out of range

D202,

1-2, ~1200 keeps climbing until out of range
1-3, 003 amusing open just something because its a semiconductor?
2-1, ~1200 keeps climbing until out of range
2-3, ~1200 keeps climbing until out of range
3-1, 002
3-2, ~1200 keeps climbing until out of range

D201,

1-2, ~1200 keeps climbing until out of range
1-3, 003 amusing open just something because its a semiconductor?
2-1, ~1200 keeps climbing until out of range
2-3, ~1200 keeps climbing until out of range
3-1, 003
3-2, ~1200 keeps climbing until out of range

Also, I wasn't sure about the way the leads go if that makes a difference.

Thanks!

[tom66]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Sorry, when I mention all combinations I mean test each pair of pins both ways. It would seem ALL the diodes are failed but that would be very rare.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Sorry, when I mention all combinations I mean test each pair of pins both ways. It would seem ALL the diodes are failed but that would be very rare.

So do 12 tests on each one is that correct? Do the 6 I did but then switch leads like

D203 Top in Picture,

R1-2B,
R1-3B,
R2-1B,
R2-3B,
R3-1B,
R3-2B,

B1-2R,
B1-3R,
B2-1R,
B2-3R,
B3-1R,
B3-2R,

B=Black Probe, R= Red Probe

Is That Right?

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Also there seem to be another two on the Primary Side. Do I need to check Those?

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

I take that Back, I don't think those are Diodes.

Also I am having trouble getting a good reading I have another meter with a diode test should I use that?

[tom66]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Also there seem to be another two on the Primary Side. Do I need to check Those?

Those are MOSFETs. When they fail, they usually take out the fuse. At the moment, you don't need to test them.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

OK Also, I was getting different readings on D203 but just rounded since I thought it was the meter. Now I see why though, its not the same as the other two D202 and D201 are different than D203.

[retiredcaps]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Also I am having trouble getting a good reading I have another meter with a diode test should I use that?

Post a picture of your multimeter that you will be using from this point forward.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

Post a picture of your multimeter that you will be using from this point forward.

Here I was using both of them for the First test but the Craftsman Battery Died, I am going out in a 30min to get a new one though. So I will have the option to use either one. Whatever, you think I got the Cen-Tech mostly to check DC AMPs so I don't fry my good one.

Thanks!

P.S. Both of the Readings have been the Same in all of the test I did with both of them.

[retiredcaps]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

99.99% of the measurements we ask for are DC voltage, diode, and resistance. We usually never ask for amps measurement.

I'm very explicit when directing people to take measurements as I was once a newbie not that long ago and was unsure how to use a multimeter correctly.

[ComputerGeek]

Re: Toshibia 40rv525u Green Blinking light and questions about Caps!!

99.99% of the measurements we ask for are DC voltage, diode, and resistance. We usually never ask for amps measurement.

I'm very explicit when directing people to take measurements as I was once a newbie not that long ago and was unsure how to use a multimeter correctly.

Ok I am not sure how to measure ohms properly, I thought I recall younot being able to hold in onthere for too long