Main Board Repair of a junked LG 42LV5500 TV Reflow Oven

>> YOUR LINK HERE: ___ http://youtube.com/watch?v=nAnjxwm6ea0

Video tip: Did you know you can skip fwd bkwd 10s with the cursor Right Left keys? It will let you skip the boring parts! Click 'Show More' for schematics links description. • The first 3 minutes is about the TV and testing the SMPS TCON. Discussion of Main board starts at about 3:00 • One thing I should have done is to make some wood or plastic standoffs to support the middle of the board so that it stops flexing when the video chip warms up. • One commenter used a $7 PTC heater and set it on the video chip for like 6-8 minutes. It reaches 250c and stays there. After heating, you may want to unplug and wait for it to cool so you dont move the chip. Seem like a possible safe way to heat/reflow the chip. • https://www.ebay.com/itm/Aluminum-PTC... • Similar $15 PTC heater on AMZN https://www.amazon.com/gp/product/B07... • Link to Service Manual • http://goihl.com/42LV5500/lg_42lv5500... • Link to Main Board Schematic (for power supplies) • http://goihl.com/42LV5500/lg_42lv5500... • I was given a 2011 42in LG LED TV that had no picture and no backlight. The remove power button worked and I could hear a click. I tested the Power Supply and it was ok. I tested the LCD panel driver board, called the TCON board, and it was ok. I checked all the power supplies on the main board and they were ok. The main control CPU #IC602 (called the 'MICOM') was receiving commands from the front panel and the IR remote and was turning on the power supply, but it did not send the signal to turn on the LED backlight (INV_CTL) or turn on the local Panel 12V (Q507). I think this was because after the main power was turned on, the MICOM was trying to talk to the video processor IC101, but it was offline and was not communicating. This prevented the MICOM from going any further. I reflowed IC101 (sort of) by using a heatgun to apply heat to the video processor chip under the main board heatsink and that fixed the problem. Note that a hair-dryer will not be hot enough. If you have a really big heat gun, you will need to shield the board with metal so as not to burn the PCB. There are many video's about putting this main board in the oven to reflow the board, but I'm against this.. • Here is a video about the oven baking method: • Repair An LG Television Motherboard B... • Here is a video about a warped board. Did this happen in the oven? • Strangely warped main board from LG 4... • I would actually do some troubleshooting on your power supply and T-Con board before trying something as drastic as the oven on the main board. The oven just barely gets to the melting point of solder. Actually at 385 degrees Fahrenheit it doesn't even melt some solders. and it melts all of the solder on your board which could cause other parts to loosen up and cause more problems. I prefer the local heat method myself. I don't doubt that the board may work after the oven, but it may not be a complete reflow of the solder joints - it may just move the board or chip around a little creating a mechanical connection of the affected joint(s). • Video Chip I reflowed BCM35230KFSBG Ball Grid Array • https://www.ebay.com/itm/1pcs-BCM3523... • LG 42LV5500 No picture, not turning on, no backlight, no sound. Main board • Remote PN AKB72914042 • https://www.amazon.com/gp/product/B00... • Motion Remote PN akb73295502 • https://www.amazon.com/LG-AKB73295502... • Service Remote PN MKJ39170828 • https://www.amazon.com/gp/product/B07... • Weller 6966C 250W Electric Heat Gun https://www.amazon.com/dp/B000ICGMN4/... • Full TV Model 42LV5500-UA.AUSYLJR • Boards inside this Model TV • SMPS PN EAY62169801 • TCON comes with panel I think • Main Board PNs • EBR73146501 • BCM35230 • LA12D/E • EAX63333404(0) • Link to EAY62810801 SMPS Manual (similar PS, but NOT for this model) • http://goihl.com/42LV5500/lg_eay62810... • 42LV5500 Support Page • https://www.lg.com/us/support/product... • LG Spec Sheet • https://www.lg.com/us/products/docume... • TV User Manual (I had to add .pdf to the end of the downloaded file) • http://gscs-b2c.lge.com/downloadFile?... • The user manual lists all these models on the front cover, so this procedure may work for other models. • LED LCD TV MODELS • 42LV3700 • 47LV3700 • 55LV3700 • 42LV5400 • 47LV5400 • 55LV5400 • LCD TV MODELS • 42LK530 • 47LK530 • 55LK530 • 42LK550 • 47LK550 • PLASMA TV MODELS • 50PZ750 • 60PZ750 • 50PZ950 • 60PZ950 • 50PZ950U • 60PZ950U • 42LV5500 • 47LV5500 • 55LV5500 • 42LW5600 • 47LW5600 • 55LW5600 • 32LW5700 • 42LW5700 • 47LW5700 • 55LW5700 • 47LW6500 • 55LW6500 • 65LW6500 • 47LW9800 • 55LW9800 • 55LV9500

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