Mitsubishi WD-52525 Bliniking Timer light: Page 2


	FORUM HOME	SEARCH POSTS	WHO'S ONLINE	LOG IN	RULES F.A.Q.

TV Forums: TV Equipment: TV Repair Forum:
Mitsubishi WD-52525 Bliniking Timer light

1 2 3

View All

Print Thread

74f100
Enthusiast

Sep 24, 2013, 2:47 AM

Post #26 of 53 (1957 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Yes, seems to be a problem there.

A buzzing transformer is indicative of a short in that circuit.
HDMI not working

Hazardsneon
User

Sep 24, 2013, 4:12 AM

Post #27 of 53 (1956 views)
Shortcut

Re: [74f100] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Where would you look for a short first?

74f100
Enthusiast

Sep 25, 2013, 2:22 AM

Post #28 of 53 (1950 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Semi conductors on the power supply.
HDMI not working

Hazardsneon
User

Sep 25, 2013, 12:59 PM

Post #29 of 53 (1947 views)
Shortcut

Re: [74f100] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

I had the power board out before. I looked for a short around the power supplies and couldn't find a short. Also all of the standby voltages were present and at their respective voltages.

74f100
Enthusiast

Sep 28, 2013, 1:58 AM

Post #30 of 53 (1909 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Check the secondary circuits. If you can determine where the buzzing is coming from, that can help isolate the circuit with the problem.
HDMI not working

Hazardsneon
User

Oct 1, 2013, 12:09 AM

Post #31 of 53 (1899 views)
Shortcut

Re: [74f100] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Can you elaborate on what you mean by checking secondary circuits? Also, the buzzing is coming from from T9A10. It is the main transformer for most of the supplies.

jts1957
Veteran

Oct 1, 2013, 1:47 AM

Post #32 of 53 (1897 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Quote

12V - 0V
5V - 0.7V
3.3V - 0V

Pardony the intrusion, but if these are on the secondary of the transformer (T9A10) you just mentioned, try measuring resistance at the same points to ground. Usually is the non-transformer connected side of a diode.

Most of us here have, or are usually able to access, the service literature for people's items, so don't be afraid the mention part location numbers etc. Would save a little time and help the troubleshooting process along.

30VS / 12VS / 6VS & plus and minus 15 volts are on secondary of T9A10.

-------------------------
Location: Far, Far Away

(This post was edited by jts1957 on Oct 1, 2013, 1:53 AM)

Hazardsneon
User

Oct 1, 2013, 2:34 PM

Post #33 of 53 (1890 views)
Shortcut

Re: [jts1957] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

I thought that supplies on the secondary of the transformer is what was asked of me but I wanted to make sure.

I used the Anode of D9A30 for my ground reference.

12V - 1.272k ohms
5V - 1.77k ohms

I made the resistance measurements quick this morning before I took off for work and I measured the 3.3V but forgot to write it down but it was above 1.7k.

Could it be that the switcher is fatigued and when the whole system starts to initiate, the switcher fails? I had the power board out before and when powered up, with nothing plugged in, the voltage rails were as they should be.

74f100
Enthusiast

Oct 2, 2013, 12:01 AM

Post #34 of 53 (1884 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Yeah, jts is right on what I was asking.

Are those measurements with the power supply out or in circuit? The resistance should be close, there isn't a standard out on what they should measure. But you would be looking for a short or near short on any of those secondaries. If it was out of circuit, reconnect it, and see if any of the low lines then reads near shorted.

Sorry for the slow replies, I'm working a lot of hours, supporting half the neighborhood, and rebuilding my wife's transmission (in her car of course). So if anyone has any experience rebuilding Honda transmissions, shoot me a pm.
HDMI not working

Hazardsneon
User

Oct 2, 2013, 1:23 AM

Post #35 of 53 (1881 views)
Shortcut

Re: [74f100] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Everything was still connected, obviously without AC power. None of them were near shorts.

74f100
Enthusiast

Oct 2, 2013, 1:48 AM

Post #36 of 53 (1879 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

What voltages are coming from the "suspect" transformer? I don't have access to Mitsu from home, so I rely on what you tell me.
HDMI not working

Hazardsneon
User

Oct 2, 2013, 4:30 AM

Post #37 of 53 (1876 views)
Shortcut

Re: [74f100] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

T9A10 provides the 30VS, 12VS, 6VS, +15V and -15V.

74f100
Enthusiast

Oct 3, 2013, 12:54 AM

Post #38 of 53 (1868 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

And the 12 v is the only low one?

If so, disconnect the wire or connecter for that line only and see if 12v comes up at the diode.
HDMI not working

Hazardsneon
User

Oct 3, 2013, 1:07 AM

Post #39 of 53 (1866 views)
Shortcut

Re: [74f100] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

No, they are all low.

jts1957
Veteran

Oct 3, 2013, 1:20 AM

Post #40 of 53 (1864 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

In Reply To

Voltages as follows:

30VS - 27V = OK
+15V - 10.6V = Low
-15V - -10.7V = Low
12V - 0V = ?12VS? Missing
5V - 0.7V = (6VS is needed for 5V supply)
3.3V - 0V = (12VS is needed for 3.3V supply)

When the buzzing occurs the voltage is building and when it stops, all the voltages drop. It is a transformer on the power board that is buzzing.

-------------------------
Location: Far, Far Away

(This post was edited by jts1957 on Oct 3, 2013, 1:30 AM)

74f100
Enthusiast

Oct 3, 2013, 1:29 AM

Post #41 of 53 (1862 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Start with the 12v line. See if that one comes up, and the low ones come up with it.
HDMI not working

Hazardsneon
User

Oct 4, 2013, 12:25 PM

Post #42 of 53 (1851 views)
Shortcut

Re: [74f100] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

So, without removing components, the only way that I could disconnect +12VS is by un-plugging K1. I unplugged K1 and 12VS was at +12V and 6VS was at +6V.

Then, since K1 spreads out the 6VS and 12VS to the DMD, Signal, FMT, and Terminal boards, I proceeded to disconnect their respective 6VS and 12VS connectors.

When I disconnected the supply to the Signal board, the 6VS read +3.2V and the 12VS read +6.5V. None of the others had any effect on the supplies.

Hazardsneon
User

Oct 6, 2013, 5:22 PM

Post #43 of 53 (1838 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

I just plugged the Signal board power back in and disconnected K3 (goes to the signal board) and it has the same effect as if I had the power removed from the signal board.

I'm guessing that the signal board is powering on the non-standby supplies and it's having issues but I checked for low resistance on the 12V,5V and 3.3V and they were all up in the kilaohms.

Also, the transformer doesn't stop buzzing completely until I unplug K1. I'm guessing that the switcher is damaged and can't drive the current. I will be ordering a new one and report back.

Hazardsneon
User

Oct 15, 2013, 2:15 AM

Post #44 of 53 (1820 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

So I didn't end up installing a new switcher IC but I finally got around to doing a quick load test.
I had the power board out of the TV and on the bench at work.
When I plugged the power in, all of the supplies were at their proper voltages except for the -15 which was dead. I put a 10 ohm load on the 12VS and it drug the supplies down to near 0. I don't know how much the system usually pulls on the 12VS system but there is a 15A fuse on the circuit and I was only pulling 1.2A and it killed the supply.

What would cause this issue?

jts1957
Veteran

Oct 15, 2013, 3:58 AM

Post #45 of 53 (1819 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

If one supply is on, they should all be on.
Check F9A04.

What do you mean by "killed the supply?"

-------------------------
Location: Far, Far Away

Hazardsneon
User

Oct 15, 2013, 4:34 AM

Post #46 of 53 (1817 views)
Shortcut

Re: [jts1957] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

When I meant "killed the supply" I meant that the voltages dropped and after I removed the load, the voltages came back up. All fuses are measuring around 0 ohms.

jts1957
Veteran

Oct 15, 2013, 4:44 AM

Post #47 of 53 (1816 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

DC voltage across C9A40?

-------------------------
Location: Far, Far Away

Hazardsneon
User

Oct 15, 2013, 4:17 PM

Post #48 of 53 (1812 views)
Shortcut

Re: [jts1957] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

The DC voltage across C9A40 is 8.37V

jts1957
Veteran

Oct 15, 2013, 7:24 PM

Post #49 of 53 (1805 views)
Shortcut

Re: [Hazardsneon] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

Quote

all of the supplies were at their proper voltages except for the -15 which was dead.

You are NOW saying that your NEGATIVE 15 volt supply is measuring POSITIVE 8.37 volts ... Definitely not dead, and shouldn't be positive at any time.

Are you using the correct ground point as your reference? (+ 15 & - 15 are one ground point ... the rest of secondary voltages are a second different one.)

-------------------------
Location: Far, Far Away

Hazardsneon
User

Oct 19, 2013, 2:41 AM

Post #50 of 53 (1795 views)
Shortcut

Re: [jts1957] Mitsubishi WD-52525 Bliniking Timer light [In reply to]	Can't Post

I was previously measuring from the wrong ground point but it doesn't matter much now because all of the supplies are back up and running.

I pulled C9A21, one of the timing caps near the switcher and it was completely open. I replaced it and it is running like a champ.

Now another problem UGG!

When I powered it back up with the newly working PS board, the speakers made a horrible loud hissing/humming sound. At first I thought I put one of the caps in backward and I was boiling the electrolyte but I disconnected the +15 and -15 supply for the audio and the sound went away.

So now, as the TV sits, the speakers make a loud noise, the cooling fan for the chassis starts up and then shuts off and the status light is red. The power button does nothing still.

I promise that I will try to be more thorough on my measurements. I really appreciate that you are taking your time to help me!

1 2 3

View All

Print Thread

Search for (options)

- Page loaded in: 0.25 s on (CGI/1.1)