VZ42L No Amber light, no stand by 5v

[budm]

Re: VZ42L No Amber light, no stand by 5v

OK. that is what I expected on Pin 8 (vcc) is 1.8 Ohms which is shorted? If it is, it is bad. Pin 7 also way too low. Next thing to do is to remove the IC and take the reading on pin 8 pad and 6 pad to see if the resistance will go way up.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Ok I attempted to remove the ic . I desoldered it completely and when I used my ic puller the chip just cracked!! There was a weird brown residue left under the chip. The pads are all pretty good just screwed up the chip I will order another one is there anything else I should order

[budm]

Re: VZ42L No Amber light, no stand by 5v

I need you to take the resistance reading between of the pads pin 6 and 8, pin 6 and 7 (this one is to verify if the Gate of the MOSFET is shorted the Source or not, important test.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

6-8 1.5m
6-7 ol

[budm]

Re: VZ42L No Amber light, no stand by 5v

OK, that is good readings, I would order a couple ICs in case it gets damaged from soldering.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Ok great ordering now I will let you know when they come in THANKS so much

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

My parts will be arriving this evening should I solder it in and try powering it on or should I leave connectors off and test for 24v and 12v first? Thanks

[tom66]

Re: VZ42L No Amber light, no stand by 5v

Connected up is fine.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

OK Installed new IC and nothing has changed. I am still not getting the 24V or the 12Vat the connector. Also the Cap is still only giving me 160V DC? I have retaken the resistance measurement with he new chip and GND is not shorted to VCC .

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Please let me know what else you suggest checking Thanks so much

[tom66]

Re: VZ42L No Amber light, no stand by 5v

This is with PSON signal high? (>2VDC)

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Yes pson is 3.127v

[tom66]

Re: VZ42L No Amber light, no stand by 5v

OK, with PSON high, what do you measure -across- the Vcc and GND pins of the replaced IC? You can measure a nearby capacitor which is connected to Vcc if it's hard to access the chip from the top.

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

When I plug tv in the big brown cap gets up to 160v. I press power button and Visio light changes from amber to white but the cap stays at 160 pson goes up but 24v pins and 12v pins stay at 0

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Sorry I will go check that now I responded same time as you

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

13.71v

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

The datasheet says operating VCC 10-22 volts

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

I guess I am not good enough at tracing circuits to check the device that is being powered by the output of this chip?

[tom66]

Re: VZ42L No Amber light, no stand by 5v

This is L6562D you replaced?

[Bigredram87]

Re: VZ42L No Amber light, no stand by 5v

Correct