Wimius P20 projector won't turn on

• Wimius P20 projector won't turn on
  Posted by veskom on 28 Apr, 2024 15:07
• Hi,
  I have Wimius P20 projector given to me by friend that would not turn on. I have verified all the fuses, and voltages, and verified that 5V and 14V are going to the main board. But indicator LED is not coming on.
  I have visually inspected the board and nothing suspicious cis coming out. There was some whitish deposits on the HDMI connections on the board, but after cleaning with IPA all cleaned up, and there are no signs of damage.
  I have watched many repair videos on YT and kind of understand troubleshooting process, but for one, there is almost none for this Wimius P20, nor any documentation on the board or any service manuals.
  I do not have thermal camera, but tried to use touch method, and only one section is getting hot, not right away, but after a minute or two, it starts feeling hot, it is Inductor labeled 4R7 (also labeled L4 on the board) and not sure what it is, but most likely some voltage regulator, labeled i206 (or 1206 with dot on top of the one and underline under 0), also labeled U102 on the board.. It is SMD component in SOT-23 with 5 pins (picture attached).
  I have measured voltages... and output voltage is 0.7 volts, same voltage that goes to the controller board where "Power ON" button is and indicator LED (which does not turn on).
  As You can see from the picture, there are 2 same SMD components on the board, and same Inductors, but the other oned does not get hot. And output voltage on that regulator is 1.2 V. Both have input of 5V.
  
  If you can help me identify this component, and maybe I can make sense of the measurements, and help me find the short (which I believe it is), and point me to the right direction.
  
  P.S. My brother was into electronics, and he was great help to me, but he recently passed, and I have no where to turn for help on this mater. And you can ask your brother stupidest questions without being judged, so sorry if I misuse this forum.
  
  Thanks,
  
  Vesko

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• #1 Reply
  Posted by m k on 01 May, 2024 16:44
• If both are boost converters their output should be above that 5V.
  
  There seems to be a third converter, S-E corner of the panel connector.
  
  Who knows how many voltages there should be, but that 0.7V is very low.
  Nothing wrong with low voltage in principle, but for power LED.
• #2 Reply
  Posted by veskom on 01 May, 2024 18:28
• Hi,
  
  This one has label 6817D 0AA2R, again no results on the web for it. Similar as others 5V input and all other measurement are in mV.
  
  But there is newest development. There is one CAP next to the TEMP connector, C21, if I press hard, or if i lick my finger and touch that CAP, projector light comes ON. Only that, nothing else. Projector lamp is powered straight from the power supply as it requires quite a lot power. This CAP has 14V on one of the connectors.
  
  On the main board, except previously mentioned components, also CPU is getting hot. Nothing else. I am not sure if CPU is dead, or there is some short/break in the circuit.
  
  Regards,
  
  Vesko
  
  
  

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• #3 Reply
  Posted by m k on 02 May, 2024 09:55
• Those regulators/converters can also have an on/off function.
  Means that they are not starting until something is giving an order.
  
  So top right corner is for controller board?
  CN15 seems to have a switch BL_SW.
  
  How is Q1 connected?
  Q1 right seems to go to CN15 pin1 and pin2 is GND.
  Is the text above C22 BL_VCC?
  CN15 pin3 seems to go to Q1 top left, bottom left goes somewhere around CN16.
  CN15 pin4 is a bit uncertain.
  
  2nd GND can be a protection.
  There pin4 GND is master so that pin2 GND is not present before CN15 is connected.
• #4 Reply
  Posted by veskom on 03 May, 2024 20:48
• Hi,
  
  Thank You for your help. After messing around with the board in the area where it was getting hot, by applying flux, and trying to re-float that voltage regulator, or whatever it is labeled i206 or 1206, board near the connector started burning (red hot) which after that I guess board is useless.
  
  Oh well.... RIP Wimius P20 main board.
  
  Thanks You for your help.
  
  Regards,
  
  Vesko