Picked up a cheapy Panasonic Plasma TH-P46U20A.
Symptoms- dead, no LED, no relay clicks etc. My expectations were this could be mainboard failure.
Found no standby voltage, and no input A/C voltage on D501 standby rectifier.
Fuse F501 T2AH250V was open. ( Panasonic # HU215002BEP )
I did a quick probe around the standby cct and found nothing shorted so hoping it was a surge gave it the benefit of the doubt and pulled a fuse off a spare board.
Powered it up and there was light arcing around the area of IC501, the fuse blew. Double checked and still no dead short but pulled the board right out looking for burns.
In the shadows under IC501 I could see a bit of black between pins 2 & 3. So i pulled this IC out and also out of a good board. Between 1 & 2 the resistance was about the same, between 2 & 3 on the clean one it was 7 - 8 meg, on this sooty one it was about 2kohms.
So I cleaned it up with acetone and scrapped off any residue and it changed to being 7-8meg again. So the IC MIP3E50MY (marked MIP3E5MY) had not blown just the casing had become conductive.
I can only guess at the cause , either dust build up or even an insect got in there and burnt causing carbon tracking.
So replacing the fuse, I swapped an IC into it from another board and it's all good.
I've sleeved the legs with heatshrink on the old one and when I get some fuses I'll test it out.
Also I believe these color banded fuses the OEM brand is SkyGate Co Japan, Littelfuse have a similar spec product.
SG5063 series number 002 or SG5063002 for the 2Amp
Littelfuse 0215002.MXEP, 0215002.MXESPP
For a 2010 model, hardly used at 4400hrs. Not a bad picture too for an entry level FHD. This has the TNPA5105 SC in it.
Symptoms- dead, no LED, no relay clicks etc. My expectations were this could be mainboard failure.
Found no standby voltage, and no input A/C voltage on D501 standby rectifier.
Fuse F501 T2AH250V was open. ( Panasonic # HU215002BEP )
I did a quick probe around the standby cct and found nothing shorted so hoping it was a surge gave it the benefit of the doubt and pulled a fuse off a spare board.
Powered it up and there was light arcing around the area of IC501, the fuse blew. Double checked and still no dead short but pulled the board right out looking for burns.
In the shadows under IC501 I could see a bit of black between pins 2 & 3. So i pulled this IC out and also out of a good board. Between 1 & 2 the resistance was about the same, between 2 & 3 on the clean one it was 7 - 8 meg, on this sooty one it was about 2kohms.
So I cleaned it up with acetone and scrapped off any residue and it changed to being 7-8meg again. So the IC MIP3E50MY (marked MIP3E5MY) had not blown just the casing had become conductive.
I can only guess at the cause , either dust build up or even an insect got in there and burnt causing carbon tracking.
So replacing the fuse, I swapped an IC into it from another board and it's all good.
I've sleeved the legs with heatshrink on the old one and when I get some fuses I'll test it out.
Also I believe these color banded fuses the OEM brand is SkyGate Co Japan, Littelfuse have a similar spec product.
SG5063 series number 002 or SG5063002 for the 2Amp
Littelfuse 0215002.MXEP, 0215002.MXESPP
For a 2010 model, hardly used at 4400hrs. Not a bad picture too for an entry level FHD. This has the TNPA5105 SC in it.
Attached Files
Comment