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Old 10-27-2020, 09:14 PM   #45
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Join Date: Feb 2010
City & State: S.F. Bay area
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Default Re: Tefal GV8962 Pro Express steam iron - no power

Originally Posted by beetle1303 View Post
Arh... indeed, one end of R1 solder joint is done poorly.. Reworked, and now D pin & C1 (I believe not C4) get 325Vdc, and C2 gets 24Vdc.

But pressing the power on/off button still no led light..

*Noted on R1 being a 100 ohm resistor, should get a 2W 8-10 ohm replacement?
At this point you can leave the 100 Ohms resistor for testing for now.
So the 24V buck converter is working now, now we need to trace out the other power supply section for low Voltage that is used for running those IC's (U3, U4) next.
So look up the part number of some of those IC's so you can look up the spec sheet to locate the VCC pin of the IC then you can find out if the VCC is present or not for the IC's to run.
Check Voltage of U2, it looks to be LDO Regulator IC.
I also see some bad solder joints, one looks burnt, others you can see ring developing around the joint, so look for ring around the solder joints and resolder them.
BTW, that small white connector, what is connected to that connector?
Attached Images
File Type: jpg Bas solder joints.jpg (496.7 KB, 3 views)
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Basic LCD TV and Monitor troubleshooting guides.

Voltage Regulator (LDO) testing:

Inverter testing using old CFL:

Tear down pictures : Hit the ">" Show Albums and stories" on the left side

TV Factory reset codes listing:

Last edited by budm; 10-27-2020 at 09:39 PM..
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