Mitsubishi V26 chassis (1st gen DLP) capacitor failures

[lcaillo]

There seems to be a pattern of failure of many capacitors in this chassis series. Problems that relate to these failures are the failure to complete boot cycle (timer LED blinks continuously) and a number of startup issues including lamps not starting or shutting down. The most obvious manifestation of the failures are swollen or vented caps. We have seen sets with a dozen or more swollen capacitors. Many more are often on the way to failing, demonstrating low capacitance, high dielectric absorbtion, high ESR, or d.c. leakage. These caps are the conventional radial polar electrolytics made by Jamicon.

Additionally, some of the problems with lines in the picture may be due to problems with surface mount capacitors. We have found caps on the DM that appear to be thermally sensitive, and have high ESR.

One can speculate as to the reason for these failures, but it seems certain that all of the radial polar electrolytics made by Jamicon are suspect. Virtually all that test are marginal or test bad, even if they are not swelling. I recommend replacing all of the following caps.

The most reliable brand and supplier at the best prices that I have found seems to be the Panasonic caps from Digi-Key. Use the longest life, lowest impedance, 105 degree caps available in the right size and value.



Terminal 1 board
CL203 1000uF 10V

Terminal 2 board
C2M28 1000uF 10V
C2M29 1000uF 10v

FMT board
C8F19 1000uF 16V
C8F21 1000uF 16V
C8F22 1000uF 16V
C8F27 1000uF 16V

DM board
C81A2 1000uF 16V
C81A3 1000uF 16V
C81B3 1000uF 16V
C81B4 1000uF 16V

Signal board
C8788 330uF 16V
C8738 330uF 16V
C8717 330uF 16V
C8761 330uF 16V
C8780 330uF 16V
C8798 330uF 16V
C87A3 330uF 16V
C8797 330uF 25V
C8710 330uF 10V
C8727 330uF 10V
C87A0 330uF 10V
C87A7 330uF 10V
C3E51 470uF 35V
C3E52 470uF 35V
C3E53 470uF 35V
C3E54 470uF 35V

Power Supply
C9A52 1000uF 16V
C9A59 1000uF 16V
C9A61 1000uF 16V
C9A62 1000uF 16V
C9A39 2200uF 35V
C9A40 2200uF 35V
C? 3300uF 16V
C? 3300uF 16V

[lcaillo]

After servicing a few of the sets that have capacitor problems, I am more convinced that the problem is going to be more complex to solve than just replacing the radial caps. Mitsubishi is obiously recognizing this, as they have been providing at least partial assistance on the cost of repairing the problems for many clients.

As an experiment on a WD-52725, which had a repeat failure (flashing timer LED, failure to boot DM) after replacing all of the radial caps, I began testing the surface mount caps on the DM. I tested most of them in circuit and found many that looked bad, so I decided to start pulling them and testing them out of circuit. I used a Sencore LC105, which tests four parameters, capacitance, ESR, dielectric absorbtion, and dc leakage. These are the values for the caps I tested, listed following the location and stated value of each capacitor.


Surface Mount Caps
DM board
C81B3 220uF 6V 136uF 525ohm 9% 0.37uA low capacitance, high ESR, marginal DA
C81B8 220uF 6V 144uF 176ohm 6% 0.45uA low capacitance, high ESR
C7002 220uF 6V 189uF 2.2ohm 6% 248mA marginal capacitance, high leakage
C7003 220uF 6V 195uF 2.5ohm 7% 243mA high leakage
C70C3 100uF 6V 56uF 15.9ohm 7% 13.8uA low capacitance, high ESR
C70C4 100uF 6V 61uF 15.8ohm 6% 13.2uA low capacitance, high ESR
C70B4 100uF 6V 51uF 19.6ohm 7% 1.1uA low capacitance, high ESR
C70B5 100uF 6V 29uF 41ohm 9% 0.9uA low capacitance, high ESR
C70B1 47uF 6V 6uF 42ohm 10% 0.6uA low capacitance, high ESR, marginal DA
C70C1 47uF 6V 23uF 23ohm 8% 0.7uA low capacitance, high ESR


more to come, many more tested...

Yes ... and ask me how I know this? My Mits WD-52725 was just returned to me today by the Home Theatre Store (where I originally purchased the TV). This TV is on it's 3rd replacement bulb, the Thermal Sensor has already been replaced and today, the reason for repair was (and I will quote from the repair ticket) "Unit needed new chassis/DM Module". THANK GOODNESS we purchased the extended warranty on this TV when we bought (for $3100) in Jan. 2005. According to the repair ticket, the cost for this latest (chassis) replacement was $1,223.23 (including labor, travel and tax). There is just no excuse for an expensive TV like this to have so many problems. Right now I am thrilled with the picture quality and everything seems to be working fine. BUT I am not dumb enough to think this will be the end of our problems. I understand there is a class action lawsuit pending on these units in California right now. WHAT A DISAPPOINTMENT THIS TV HAS BEEN. WE WILL NEVER PURCHASE ANOTHER MITSUBISHI PRODUCT AGAIN ......

[lcaillo]

The point of this thread was not to generate such rants. The fact is that we sold dozens of these and only a few have had problems. Mitsubishi is, for now, still one of the better products to have. The point is to better deal with the problems that do exist.

Now if you want to discuss your particular issues, and learn more about what might be going on with your set, I will be happy to do so, but let's stick to facts rather than emotional rants.

lcaillo wrote:

The point of this thread was not to generate such rants. The fact is that we sold dozens of these and only a few have had problems. Mitsubishi is, for now, still one of the better products to have. The point is to better deal with the problems that do exist.

Now if you want to discuss your particular issues, and learn more about what might be going on with your set, I will be happy to do so, but let's stick to facts rather than emotional rants.

Sorry about the rant .... needless to say, I am EXTREMELY frustrated. Would/can you believe that since I posted my response to your original post the TV has already malfunctioned? I now have the flashing green timer light of death again. I have unplugged the TV from the wall for 30 minutes, then plugged it back in. The timer light immediately starts flashing and I am unable to turn the TV on. I have already notified the service/warranty folks. When I mentioned your post to them concerning the Jamicon capicitors possibly being defective, they brushed me off and said their course of action is to order yet another new chassis Board from Mitsubishi. In other words, they do not attempt to replace the capacitors .... rather their solution is to replace the whole (defective) Board with another whole new board? I am at my wits end with this. Any advice you might provide will be appreciated.

Leonard .... one more thing .... since my earlier post to you this afternoon, I have called Mits Customer Relations and they informed me that Mits "no longer even makes new chassis for the DLP tvs". Instead they provide "rebuilt chassis" to the service technicians?? In your opinion, should I print off your post on this board and give it to the service technician when he comes to pick up our TV for this DM Module repair? I figure if he works on these TVs he should already know the capicitors on the Mits chassis are defective but maybe he doesn't know this? I am at a loss .... just frustrated with all the problems and don't know what to think. Look forward to your response ....

Vicki (gohorns1)

[lcaillo]

It would likely be pointless. Your tech will likely not be willing to rebuild the chassis. Most are too lazy and just use what the vendor sends them. Most techs are just board swappers these days. If he does not already know about it he does not do his homework and does not want to bother. They will just milk the extended warranty company until you insist on a replacement set, then move on.

No manufacturers continue to make new boards for sets out of production. They make a certain number based on the expected failure rates, then when they are gone, that is it. They require return of the old boards in some cases, rebuild them, and sell them again.

As I stated above, I wonder if all these people that are getting rebuilt boards from mits are getting the same old caps that will continue to fail.

Thank you for the list of the caps. But since I'm a rookie at this cap stuff.. I hope it wouldn't be too much trouble to tell me the part numbers for those Panasonic caps from Digi-Key that you recommend... It would help me out alot when ordering..

I have already taken my WD-62825 apart, and it looks like the following 2 caps are swollen;
C8780 from the signal board
C9A37 from the power board

But after reading your post, I'm thinking of changing out most of them..

Thanks
#2

[lcaillo]

Yes, it would be too much trouble. I go to great lengths to provide useful information and spend lots of my time replying to posts and moderating here. I gave you a great deal of info about the caps, and even gave you a suggestion for a supplier.

The point of the post is that you should change all of them if you change any at all. If you just change the ones that you think are bad, you will be getting back into it later. That might not be a big deal with most sets, but with this one the disassembly is troublesome and the risk of damage to delicate cables quite high.

lcaillo wrote:

It would likely be pointless. Your tech will likely not be willing to rebuild the chassis. Most are too lazy and just use what the vendor sends them. Most techs are just board swappers these days. If he does not already know about it he does not do his homework and does not want to bother. They will just milk the extended warranty company until you insist on a replacement set, then move on.

No manufacturers continue to make new boards for sets out of production. They make a certain number based on the expected failure rates, then when they are gone, that is it. They require return of the old boards in some cases, rebuild them, and sell them again.

As I stated above, I wonder if all these people that are getting rebuilt boards from mits are getting the same old caps that will continue to fail.

Leonard ... my TV was returned today from having the 2nd chassis replaced (Mits. WD-52725 DLP TV). I am now getting a message on-screen that reads as follows (I will quote): "HDTV does not support HDCP. Disconnect HDMI and use YPrPb connection to continue watching TV". The only way we can now watch TV is to run the cable directly to the TV and not use HDMI?? I have already called my ext. warranty people and they gave me (yet another) claim # .... my question to you is do you have any theories on what might be causing the HDMI to be non-functional? Could it be some defect in the replacement chassis they recently installed? Many thanks for any advice you might offer.