I just changed lamp on 4.5 year old Mitsubishi WD-62525 without any issues...except the yellow light remains on. Through research I learned I needed to check filter and lamp doors to be sure they are closed correctly...but we get a picture so we know these cannot be the cause. Any solutions?

If one light is blinking (lamp light?) remove and inspect lamp to make sure it is in correctly and not shattered. If the set has a recessed reset button on front (if set is unplugged and plugged back it should blink green for about 70 seconds and go out) you may have a issue there.

The model indicated here has a host of problems.

The caps on the power board have failed most likley. The V26 Power repair kit from www.tvrepairworld.com should solve the issue in most cases it does come with detailed repair instructions.

This is a common issue for DLP TV's the bulbs they have are made to last 2000-4000 life hours for Osram lamps this is the lamp the Mitsubishi usually uses so depending how old the lamp is this could be your problem I found the lamp you need for a good price

http://cgi.ebay.com/MITSUBISHI-915P020010-LAMP-PHILIPS-WD-52525-WD52525-/330465131739?pt=LH_DefaultDomain_0&hash=item4cf141bcdb

The lamp cover isnt secured properly that what causes the staus light to blink yellow.

When the lamp goes on a DLP you get no picture, if the light came on and you still had a pic then it might have been telling you ,you had other problems. If the TV wont come on now check your bulb it might be blown this time. The bulb will have lots of small peices of glass in it when its blown. They should last a few years each (3-4).

Check that the lamp door is closed all the way. There is a saftey switch that closes from the door being on all the way. If not the status light will keep blinking. There is also a switch on the air filter door.

I doubt that it is the optical assy. it sounds more like a chassis problem either on the DM or the FMT board.

check out www.tv-techs.com
if it is a chassis problem it will cost about $250.00 plus shipping one way to fix the chassis

There is a tiny reset button to the left of the timer light. Press with a pin or something small, wait 60 seconds. Viola!

I looked up the manual online - after you replace the bulb, you need to reset the bulb life timer. Using the TV remote push the menu button, SETUP menu, select the lamp reminder option to reset the hours to zero. That might help the status indicators.

Have you Checked your Ballast or thermal fuse?