AUO 11303 LCD TV T-Con IC Faulty

 

AUO 11303 LCD TV T-Con IC Faulty

 

 

 

 

 

 

 

 

 

 

 

 

This Changhong LCD TV came in for repair with the complaint of no picture but have sound. In fact when you look closely at the screen you will be able to see the backlight was lighted. There can be few causes of such problem.

Instead of guessing what might be the cause, I opened the TV cover and checked on the power supply DC output voltages. All DC output voltages were found to be correct.

The next check was on the T-con board IC (AUO -11303) and the cable connection. I reheated the T-con IC and reseated the cable (and cleaned the connector) and the problem turned out to be the same. When I turned the TV On, I could only saw the backlight lighted without any picture-see the three photos below:

Next step was to replace the AUO-11303 IC directly and retest it.

After the replacement of the ic, the picture came back normal-see the photo below 

 

Conclusion- If the power supply DC output voltages are good then focus on the T-con board. Check the VCC supply to the T-con board IC and make sure the IC is not too hot to be touched and reheat it.

If the problem still not resolved then direct replace the IC and retest it. If after the replacement of the IC and still not be able to repair it, the next step would be to find out the service manual and start checking the important signals pin in the T-con board.

 

 

Microwave Repair (failed interlock switch)

 

Microwave Repair (failed interlock switch)

 

 

 

 

 

Microwave oven kept blowing fuses and upon opening it was obvious the top interlock switch was no longer working.

Rather than order the cheapest replacements I opted to get some quality units at considerably higher cost due to the claims:

• “These are built quite a bit more robustly in our opinion”

• “Quality Item, Will Outlast Original by Years”

as I wanted the repair to last.

Only the top (of three switches) had failed but I replaced both the top and bottom as they were of the same type (normally open) and I could combine shipping; the middle (normally closed) I left

Fast forward a few months and it was blowing fuses again, often when the door was opened after the cooking had completed; made me suspect the middle switch that I had not replaced, but upon inspection it was the top switch again, even though I had invested in a supposedly better made unit.

Opening it up showed that the switch was in good shape internally but that the actuation finger was made of a plastic that had melted where it touches the switch mechanism.

The fix was interesting in that I then took the actuation fingers from the old cheap switches which seemed to be of a plastic that has a higher melting temperature and used these to replace those in the ‘superior’ switch.

The microwave is now working just fine again and hopefully will now really “outlast the original by years”. Fortunately my Wife is quite patient as I try and figure out what is wrong with broken devices around the house.