MX 4000 doesn't turn on anymore

6 replies

Hi Beoworlders,

I had recapped my MX 4000 6 months ago and it worked very well.

Last weekend my kids heard a bang and then the TV turned off. They could switch it back on once, but since then the LED turns green for less than a second it it stays off.

According to the

Hi,

TR20 = IRF624

link

Alternative IRF634, around 1 Euro... double capacity, but available ;)

link

Check all blue caps and their solder pads.

Martin

The blue caps look ok and I have checked to solder pads.

Would this be a replacement for C102:

You dont need 2000V for this cap, it's spec is just 1600V~

Use the smaller spacing.

Finally found some time to continue the work...and then suddenly my MX turned on and the picture was perfect.

But after a minute it turned itself off. No noise or bang. Just off. When I try to turn it on now, the LED flashed from red to yellew anf that's it

I have checked all soldering pads for loose connections, but seems like it can't "start up". Is this likely one of the caps? But they are all new?!

I am confused.

 

Thanks for any help!

 

Right in the middle of the "U"-Board is the service connector. Short the 2-pins and the MX can power up. All safety features are disabled.

The MX will show the error number/device... if he can show a picture.

Yes, it's not always a cap...

But beware: if you power it up, it will not power off if there is a power failure... it will stay on. So if there is something really wrong, it can burn or destroy everything. It can be a total desaster !!!

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