Haier L24B1180

[CraigR]

Hello everyone!
Well the second tv gone bad this week and I figure I best try to fix since this close to the holidays. So anyway first I have a Haier L24B1180 and when turned on I get a picture and sound for about 3 seconds then it goes off. First I checked the power board for bad caps and I pulled them out and checked with a PEAK ESR meter and all were good. I checked the resistors and were ok then the 2 transistors and seemed to be good also so as a novice I'm kind of stuck so any help would be appreciated.

[budm]

Re: Haier L24B1180

Start by posting good clear pictures of the back of the TV and the boards so we know what we are dealing with first.

[CraigR]

Re: Haier L24B1180

Ok I hope these help

[budm]

Re: Haier L24B1180

Pictures of the bottom side of the power supply-inverter board so I can give you the test points for checking the inverter transformer high voltage winding resistance test.

[selldoor]

Re: Haier L24B1180

Perhaps you can also define "then goes off" - Picture Sound power led?

Sleep timer set for 3 seconds?

[CraigR]

Re: Haier L24B1180

When it goes off I mean the picture and sound. Here it the underside.

[selldoor]

Re: Haier L24B1180

Does the power led stay on/change color

No power to the board for 5 mins meter on ohms 2000
test S1 to S2 and S3 to S4 and post results

Pictures could do with being bigger - as close to 2mb as you can get

[CraigR]

Re: Haier L24B1180

When plugged in the led is red then turn on it's green and when tv shuts down it's still green then goes out completely.
I read S1>S2 870 and S3>S4 850

[selldoor]

Re: Haier L24B1180

Looks like that is ok then -they are within 3%
Next- on the back of the board there are two components
with 2 and half legs and a tab what is the part number cant quite make it out and its pointless me guessing.

[CraigR]

Re: Haier L24B1180

There is D454A and under that is BA951D

[selldoor]

Re: Haier L24B1180

OK - I think its one of these
http://pdf1.alldatasheet.com/datashe...D/AOD454A.html

Do both have same number.?

[CraigR]

Re: Haier L24B1180

Yes both have same number. I checked them and compared them in diode mode with my meter and both read the same.

[selldoor]

Re: Haier L24B1180

This small tv is very like a monitor with a TV tuner.
It will help if you read this
https://www.badcaps.net/forum/showthread.php?t=10419
Start at post19 - test them as Mosfets and post the results as in the guide

[CraigR]

Re: Haier L24B1180

You can not see any image with a flashlight but I will test anyway.

[CraigR]

Re: Haier L24B1180

Of the 3 MOSFETS 2 are the same part number and read OL in ever position except black center and red right that reads 86.3 on 1 and 93.2 on the other and the third reads OL in every position so I switched my meter to diode mode and it reads OL except for black center and red right and that reads 533

[selldoor]

Re: Haier L24B1180

Ok - they do not seem to be shorted.
Is the connector from the main board labelled - does it have a BLon.
and have you got a 3 v battery or 2 x 1.5v
Have you checked over the solder joints on the main transformer and the inverter section

[CraigR]

Re: Haier L24B1180

3.74 volts on the BLon and checked joints under lighted magnification.

[selldoor]

Re: Haier L24B1180

Running out of tests here I dont think you are as novice as you said.
I would like to try to get the backlights to stay on (guess you would too)
With the set off first try unplugging the cable that goes from the main board to the panel and switch on.
obviously no picture but perhaps the panel is pulling the system down.

[CraigR]

Re: Haier L24B1180

Ok, took the cable to mainboard off then plugged set in and no light on front and no panel lite or anything switch made no difference. Is this correct? Or have it plugged in then pull cable?

[selldoor]

Re: Haier L24B1180

Are we on the right cable the long one with blue and white stranded at one end and looks like 4 red at the other?