Mitsubishi DLP wd65733

[GAStuntman]

I have a DLP tv with no power light, no picture, or no sound. This is my first time working on this type of tv. The voltage on the power supply seems to be right? Any suggestions?

[R_J]

Re: Mitsubishi DLP wd65733

This is not much information... What are the voltages on the plug going from the power supply to the main? There should be a number of fuses on the main board, ie: F9G00, F9G01, either check that they are not open or check the voltage on both sides of them.

[GAStuntman]

Re: Mitsubishi DLP wd65733

The fuses starting at F9G00, etc. all have voltage at 12.21

[GAStuntman]

Re: Mitsubishi DLP wd65733

The connector in the picture below has the right voltage on the power supply cable as well as the mainboard side. As stated above the fuses all have the correct voltage as well. If you like at the picture it shows where the pins should test at a certain voltage. That's what I'm talking about when I say I'm getting the proper voltage.

[R_J]

Re: Mitsubishi DLP wd65733

Does this set have a system reset button on the front panel? if not try this: Press and hold power button for 8 seconds
Do you have any voltage going to the board with the power button?
If the tv has a ACTIVITY button, press and hold the ACTIVITY and CHANNEL DOWN buttons at the same time and hold for 5 seconds, see if you get any led flashing a code

[GAStuntman]

Re: Mitsubishi DLP wd65733

The reset button didn’t do anything. I also tried holding the power button for 8 seconds & still no luck. It’s like the tv is completely dead. None of the light indicators are working. I don’t hear any noises when I plug the tv into a socket or when pressing the power button. I have read that the back panel is supposed to be connected to the tv when testing for lights. I haven’t put the back panel back on yet. I wanted to test the boards before putting everything back together. Could this be my problem?

[R_J]

Re: Mitsubishi DLP wd65733

There will be a lamp door switch that needs to be defeated if you try without the cover on. But if that switch is open it should give an error (lamp led blinks yellow)

You must be missing one of the 3.3 or 5 volts, did you check for voltage on the cable that goes to the buttons?

Look for F9G00 fuse, it supplies 12 volts to IC9G01 (pin2), its output should be 5VSL (5 volts) on pins 7&8. that should feed IC9C51 pins 8&5 (via L9g14 & L9G02 to L9C51) and output 3.3VSL on pin1

[GAStuntman]

Re: Mitsubishi DLP wd65733

Thanks. I’m getting the voltage that you suggested above. I’m still checking other pins as of now but I started with the F9G00 fuse & so far so good.

[GAStuntman]

Re: Mitsubishi DLP wd65733

The voltage checks out on the pins you suggested. I must admiythis tv has me stomped. If you think it’s a mainboard issue I’ll just replace the mainboard instead of trying to repair the current one. I know the power supply is good. Do you think ording a new mainboard will fix the tv?

[R_J]

Re: Mitsubishi DLP wd65733

I never worked on too many of the mitsubishi' dlp's, there were'nt too many sold around here. I would do some more checks before ordering a main baord. Do you have the service manual?

[GAStuntman]

Re: Mitsubishi DLP wd65733

Yes, I was able to find the service manual. I'm still trying to figure out what is causing the issue.

[budwich]

Re: Mitsubishi DLP wd65733

just like regular tv troubleshooting... you need to provide the readings and labels of ALL the pins that are shown... not just "voltages check out"... the forum can't see what you have done to say that. And just like regular tv troubleshooting... the values of the "other pins" are just as important even though they don't have "voltage labels" associated with them.... that's why you need the list of pins and measured values... with the set plugged in and then again with the set power button pressed. Then people may be able to help you get to the problem. Note: some of those pins may change during the power up "cycle" so you may need to monitor them during that event and repeat for each cycle and pin.

[R_J]

Re: Mitsubishi DLP wd65733

You may want to check around IC7A01, that is the main micro, Check that you have 3.3VSL on L7A01, that is the VCC for the micro.
KCS0 is the power button input, check voltage on R7AA9 and see if it changes when power button is pressed (one side connects to 3.3v other side goes to micro KCS0)

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