I have a SCEPTRE tv I'm trying to fix. Red light comes on solid red, but it never turns on. I checked the output voltage coming from the power supply, and all outputs are holding steady at the output voltages.
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Sceptre TV Red light won't turn on.
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Re: Sceptre TV Red light won't turn on.
"I checked the output voltage coming from the power supply, and all outputs are holding steady at the output voltages." What are the Voltages and how about signals Voltages?Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
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Re: Sceptre TV Red light won't turn on.
PS-ON is present otherwise you will not have the switched 12V, switched 24V
There are at least 3 signals Voltages, you have PS-ON, but where are the rest?
"The signal voltage is at 4.7" What is the name of this signal Voltage.
If you want help, you need to upload good clear pictures of the whole back side of the TV so we can see all the board and then the pictures of the power supply board to start with so we can see the labels of the connectors.
And where is the Model number of this TV?
Remember that we do not have the TV in front of us to troubleshoot, we are just going by your words of what you are seeing only right now.Last edited by budm; 10-01-2015, 08:58 AM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
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Re: Sceptre TV Red light won't turn on.
I can only assume something I cannot see that the BL-ON and the DIM to be 0.2~0.3V, and the PS-ON is 4.7 (The signal voltage is at 4.7 per post 3).Last edited by budm; 10-01-2015, 03:48 PM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
Comment
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Re: Sceptre TV Red light won't turn on.
O.k. I did read it wrong earlier. So it seems you do have almost all voltages. We need a nice pictures of the PSU where we can see all the pin outs. While you are at it, snap one from the main board too.
When you turn on the TV, does the back light come on? As budm suggested, measure the BLon and Dim pin too.
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Re: Sceptre TV Red light won't turn on.
Looking at the pictures, it looks like the BL-ON and the DIM signals are not routed through the power supply board connector like most TVs. The wires from the inverter boards are split, the 24V and the GND wires from inverter go to the power supply 24V connector, the BL-ON and the Dim look to be going to the main board.
He needs to look at that wires connected to the inverter board to how they are connected to the main board. I may be wrong but we need to see ALL 3 connectors of the power supply board to see how the BL-ON and DIM signals from the power supply board get to the Inverter board.
I found pictures of the power supply board from shopjimmy.
The BL-ON and DIM do not go through the power supply board.
Pictures provided by SHOPJIMMY.
http://www.shopjimmy.com/megmeet-mlt...upply-unit.htmLast edited by budm; 10-01-2015, 07:01 PM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
Comment
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Re: Sceptre TV Red light won't turn on.
You will have to look at the Inverter board connector, there should be labels for the pins.
I do not know which is your inverter board:
http://www.shopjimmy.com/catalogsear...SCEPTRE+X405bvNever stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
Comment
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Re: Sceptre TV Red light won't turn on.
PIN 12 ENA = BL-ON (<1 vdc = off, >2.5vdc = on)Last edited by budm; 10-03-2015, 03:49 PM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
Comment
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Re: Sceptre TV Red light won't turn on.
Originally posted by CapLeaker View PostAaah! Your main board doesn't send BLon, so no back light. That needs to be over 2.5V. You can try to take the BLon pin out and force the backlight on with a 1k resistor from STBY to Your ENA pin
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Re: Sceptre TV Red light won't turn on.
Originally posted by xHOBOPHOBIAx View PostThe ENA pin is staying at 50.3 mV. I tried pushing the power button while measuring this and there was no change.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
Comment
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Re: Sceptre TV Red light won't turn on.
Fixing the main board will be difficult without the diagram, all you can do is to do really good visual inspection, check the Voltage regulator ICs, heat /cool the board, etc.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
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