Hey all,
I have a Vizio E60-E3 power supply board (1p-1156800-1010) that is non-functioning. According to the last owner, it got damaged by a lightning strike or a power brownout.
I'm pretty new to repairing these sorts of things but I've had some success in the past. This one is throwing me for a huge loop though.
There's no standby voltage on the board at all. Actually, on the connector there's no voltages at all. Diodes seem intact and weren't shorted or blown, MOSFETs seem intact and testing them as diodes looked okay, but I'm not 100% sure if I've been checking those correctly. No bulging or burst caps, pretty much no sign of trouble.
I've done a little digging and the hot side of the board seems like it's mostly intact. I get some 170V across the legs of the main capacitor when it's plugged in.
I kept getting intermittent readings on one of the chips with my meter so I greenwired the trace and it stayed solid. The chip is a TEA18363T or variant thereof as far as I can tell. I get 12.4V on pin 1 of the chip and 15V at pin 5, referenced to the ground on the chip.
What's really weird is that I get a consistent voltage difference of 170V (DC) across the low-voltage transformer on the hot side. I get a 0V AC reading across the loops but this may make sense if I'm referencing ground wrong.
On the cold side of that transformer, I get nothing - no voltages anywhere. The coils are intact and read close to 0 ohms across the terminals, so it doesn't seem like the transformer itself got fried. As best as I can figure, there's a voltage potential difference but it's not oscillating therefore I get no power on the other side of the transformer?
The only other thing I've seen is a SOT-23 transistor was blown on the middle set of traces on the cold side of the board (Q201, the one I believe should be the standby voltage line). There's a few surrounding transistors that all seemed to be 2n7002 models, so I replaced it with one of those - didn't change anything though.
Pics are attached (I can annotate them if need be) - if anyone has ideas on this I'd love to hear them, this one is really stretching my knowledge. Thanks!
I have a Vizio E60-E3 power supply board (1p-1156800-1010) that is non-functioning. According to the last owner, it got damaged by a lightning strike or a power brownout.
I'm pretty new to repairing these sorts of things but I've had some success in the past. This one is throwing me for a huge loop though.
There's no standby voltage on the board at all. Actually, on the connector there's no voltages at all. Diodes seem intact and weren't shorted or blown, MOSFETs seem intact and testing them as diodes looked okay, but I'm not 100% sure if I've been checking those correctly. No bulging or burst caps, pretty much no sign of trouble.
I've done a little digging and the hot side of the board seems like it's mostly intact. I get some 170V across the legs of the main capacitor when it's plugged in.
I kept getting intermittent readings on one of the chips with my meter so I greenwired the trace and it stayed solid. The chip is a TEA18363T or variant thereof as far as I can tell. I get 12.4V on pin 1 of the chip and 15V at pin 5, referenced to the ground on the chip.
What's really weird is that I get a consistent voltage difference of 170V (DC) across the low-voltage transformer on the hot side. I get a 0V AC reading across the loops but this may make sense if I'm referencing ground wrong.
On the cold side of that transformer, I get nothing - no voltages anywhere. The coils are intact and read close to 0 ohms across the terminals, so it doesn't seem like the transformer itself got fried. As best as I can figure, there's a voltage potential difference but it's not oscillating therefore I get no power on the other side of the transformer?
The only other thing I've seen is a SOT-23 transistor was blown on the middle set of traces on the cold side of the board (Q201, the one I believe should be the standby voltage line). There's a few surrounding transistors that all seemed to be 2n7002 models, so I replaced it with one of those - didn't change anything though.
Pics are attached (I can annotate them if need be) - if anyone has ideas on this I'd love to hear them, this one is really stretching my knowledge. Thanks!
Comment