Insignia ns-32lcd tv will not turn on

[Dmoney1]

I also am the lucky owner of a insignia ns-32LCD tv. The problem I am having is as soon as the tv is plugged in the insignia light flashes from red for 2 seconds then to blue for 4 seconds and never stops, ever. The power button has no effect. I have read through previous posts and started at the power supply. I have tested the pico fuses,glass main fuse and removed and tested the 2 47mf caps, a 10mf cap near the main cap and also the main cap itself. All caps within specs. All caps also look undamaged visually.

I also temporarily disconnected the button panel to test if the power button was stuck on, but it had no effect

As far as the voltages at the ribbon cable connections on the power supply. Where I should have 5v I have 5.06v stable. All the pins where the 24v should be i do have 24.67v but, the voltages are all dropping to 10.5v in unison with the insignia power light.
I am stuck at this point
Any help would be greatly appreciated!
Thanks

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

Problem not solved. The dc voltage on the main cap swings back and forth from 265v-278v as the insignia light changes from red to blue continuously. The voltage is the same regardless of inverter connection. I did check the 2 white and 1 black fuse on the inverter and inspected the logic boards for obvious damage. I also checked that their is 5v going to the logic board and the 5v "on" signal coming from the logic board is dropping to 0v then back to 5v repeatedly. I am guessing the problem is in the logic board. Their are 2 threads from monopoly96 with the same exact problem in this forum but I think he gave up
Any help, ideas, or insight would be great. Thank you

[budm]

Re: Insignia ns-32lcd tv will not turn on

Post good clear pictures of the boards (there are more than one version of this model, there should be a dash and XX for year indication)
It sounds like that main cap is bad or the PFC Voltage booster is not working right.

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

here are a few pictures of the power supply board also I believe one of the logic boards and the entire tv. quality is not too good on the last two

[multimeter]

Re: Insignia ns-32lcd tv will not turn on

sounds like main filter capacitor to me,have had a few where there fluctuating voltages everywhere,i even tested them as good!false positive!.

everything else good,replace filter cap,your done

[tom66]

Re: Insignia ns-32lcd tv will not turn on

could also be PFC startup capacitor.

[budm]

Re: Insignia ns-32lcd tv will not turn on

Ok, disconnect the cable between the power supply board and the main board so we can force on the power supply using 1K resistor between the ON pin and the 5V pin, then check and see what you get on the main DC 450V filter cap and the 24VDC output. Main cap may be bad. Whne resistor not connected, the voltage on the main cap should be around 165~170VDC, when resistor connected, then it should kick up to 360~400VDC.
Pictures credit to Shopjimmy.

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

Ok, I found 164.3VDC on main filter cap without cable connected to main board. Once the power supply is forced on by the 1k resistor the voltage on filter cap is 342.3VDC and 24.67VDC at the outputs. Is the main filter cap voltage acceptable?

[tom66]

Re: Insignia ns-32lcd tv will not turn on

Some PFC circuit are only 350V for US version, that is OK. So, this does not happen when you press power button on TV, only when you force it on with the resistor?

[budm]

Re: Insignia ns-32lcd tv will not turn on

A little low, but at least it is stable, but right now it does not have heavy load. So we now need to force on the inverter to put heavy load on the 24V line, but I have a feeling that you main board is the problem. Connect the board back together, remove the resistor, then monitor the DC voltage on that ON pin using chassis as the Ground ref, it should have steady >2.5VDC when power switch is activated.

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

As soon as the ribbon cable from the power supply to the main board is connected the voltage at the ON pin swings back and forth from 0VDC to 5VDC. The power button has no effect on this tv. The insignia light goes from blue to red repeatedly with the change in voltage

[budm]

Re: Insignia ns-32lcd tv will not turn on

As soon as the ribbon cable from the power supply to the main board is connected the voltage at the ON pin swings back and forth from 0VDC to 5VDC. The power button has no effect on this tv. The insignia light goes from blue to red repeatedly with the change in voltage

If the 5V Standby is steady, that will explain why the voltage on the cap was going up and down, the main board is turning the power supply on and off, that ON signal should be steady. Time to repair the main board.

[tom66]

Re: Insignia ns-32lcd tv will not turn on

One thing to check first, the 24V and 12V are steady from power board?

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

Do you know what would cause this or how I can find out what is causing the main board to send this 0VDC then 5VDC signal to power supply. And yes the 5VDC standby is steady.

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

With a 1K resistor jumping the ON pin, I have a steady 24.67VDC and 17.21VDC. When the ribbon cable is connected from power supply to the main board the 24.67VDC drops 10.5VDC and the 16.7VDC drop to 2.68VDC. this cycle never stops.
The 16.7VDC is measured at the same pin where the 17.21VDC was measured. I think this is the audio output

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

Budm I don't know if the main board is actually 2 separate boards, but I'm looking at them right now. Where do I start?

[budm]

Re: Insignia ns-32lcd tv will not turn on

I just go to shopjimmy.com and type in your model number, you board should have barcode sticker on it to tell which circuit board assembly you have for your TV, you should match those numbers, you can also contact SJ to verify.
The main board is the one with bunch of input jacks on it.
http://www.shopjimmy.com/catalogsear...ignia+ns-32lcd

[Dmoney1]

Re: Insignia ns-32lcd tv will not turn on

Does any one know how to troubleshoot a main board for the problems I am having? Main board part number 782.32FB18-690C I still think this is a 2 part main board

I would appreciate any help Thank you