How to Repair a Westinghouse L1975NW 19" LCD Monitor

Intro: How to Repair a Westinghouse L1975NW 19" LCD Monitor

The Westinghouse L1975NW monitors seem to have a common failure point and this Instructable will show you have to repair this problem. If your monitor has either a blinking power LED or no power at all then this should be the solution to get it back up and running. To complete this repair you will need the following:

Tools:Phillips screwdriver, flat blade screwdriver, soldering iron, de-solder braid and a pair of tweezers.
Parts: Qty 2 40T03GP MOSFET, Qty 2 220mf 25v capacitor, 1 4amp pico fuse (surface mount)

We have a kit of all parts needed on our web site http://www.ccl-la.com/catalog/product_info.php?cPath=21_35&products_id=28

If you don't have a monitor to repair check Ebay.com, you will find them for sale usually for less than $30 in as-is condition, just be sure the screen is not cracked.

This repair guide also works for the Acer AL1916 and the Gateway Gateway FPD-1830 as these are the same monitor on the inside.

STEP 1: Back Cover Removal

First we need to remove the back cover. You can start by removing the stand, pull the little cover off the screws and remove the 4 screws under the cover. Next remover the signal cable. Now remove the 4 screws one in each corner as shown in the photos. The next step is separating the two halves of the case. Start on the side of the screen and insert the flat blade screwdriver between the front and back halves. If you apply a little pressure with the case should separate a little bit, now just work your way around the monitor. When you get to the bottom you will need to unplug the two speakers from the control board before the case will separate.

STEP 2: Getting to the Electronics!

Now that the plastics have been removed we need to get to the power supply board. Turn the monitor over face down. Remove the ten screws and nuts as indicated by the yellow arrows, and unplug the backlight tubes - red arrows and remove the metal shield. You will see the power board on the left and the driver board on the right. Unscrew the power supply board and remove it from the reset of the unit.

STEP 3: Lets Do Some Soldering!

With the power board out we can see the blown capacitors that are the cause of the problem ( the 2 parts marked by yellow squares on the right side). When the capacitor go out the damage the MOSFET transistors and that causes the fuse F200 to blow. If you look at the top of the capacitors you should see s slight bulge, that is the easiest way to find damaged capacitors. You will need to replace the capacitors and MOSFETs and the fuse on the bottom of the board. When inserting the capacitors be sure to replace them with the polarity correct, you can see the negative stripe on the side of the capacitor. After the caps and MOSFETS are replaced you will need to turn the board over and replace the fuse marked F200 on the bottom. This where you will need the tweezers because this is a very small fuse, about half the size of a grain of rice.

STEP 4: It Works! ! !

After all of your bad parts have been replaced just re-assemble the monitor and test your work. If everything goes as it should then you now have a working monitor.

Be sure to check out our web site at :http://www.ccl-la.com/monitor_repair.htm for repair guides for other monitors. We are adding guides as soon as we get them laid out.

With luck your monitor should now last many more years.

If you have questions please contact me at:

Buddy Mcsparrin
Corporate Computer
WWW.CCL-LA.COM

Comments

[Printerpenguin]

Does anyone know where I could find a schematic for the power board? (The second largest capacitor on my was bulging, but due to damage I can’t read the uf and voltage on the side, so I’m trying to figure out what uf and voltage it is so I can replace it)

[K-MartFix]

is the "parts kit" still available for this unit? I am in dire need!
thnx,
KM

[waderdog]

Hello!
With THIS monitor for a year or so when pushing the power button, the monitor would power up then off quickly several times and then usually stay on until the next session where I would have to do the same thing - keep pushing the power button on and off until it came on and stayed on. Today - no such luck. No power at all. Westinghouse LCD Monitor Model:
LCM-19V7. I was wondering if this "How To" is the same thing as the problem that I have. I would like to try this repair but I don't want to buy the parts if it's not the same problem. Any help will be appreciated!

[mustwatchtv]

on the mosfet what should I buy..it has 2 numbers on it, 1 is 712115 and the other is 40t03gp...for the L1975NW

many thanks

[jodo901]

Thanks you so much for this tutorial. It was a little nerve wracking especially the two times I "lost" the fuse. Once on my carpet and once on my work bench. But my monitor is now back up and running so I am extremely happy. It was definitely worth the $12 and the hour or so of my time to fix it. And I owe it all to this post cause I never would have known how to fix it otherwise.

Some tips for anyone giving this a go. The positive lead on the capacitors is the longer one. The negative is marked by the bar stripe on the capacitor and the shorter lead. The replacement MOSFETs are much smaller, but the proper orientation for them should be obvious. Make sure you have something that will hold on to that damnable fuse, and don't apply too much pressure holding it down or it may pop of the board like a tiddly wink and you may never find it again. Lastly be careful with the heat as the board traces are a bit cheap and will come up easily. It's better to take your time and have positive results. If you become frustrated or impatient at any point walk away for five minutes. Thanks Again!!!

[Chu Guk]

Hi, I’m experiencing problems with my LG Flatron Wide. The screen comes on with a very faded picture and then goes black. I assumed that maybe the capacitors (like for others) needed to be changed. However, I have opened the monitor and the caps look perfectly fine, no bulges or anything. Does anyone think I should just go ahead and try changing the caps anyway? Or could anything else be wrong? Thanks a lot.

[cptnKirk]

cptnKirk says:
Hello all,
I have followed the steps here and have looked at caps there are 6 side by side that are poped up is this bad news or just replace them all? and MOSFETS as well?
Ok with further looking i see no MOSFETS as in your picture my monitor is westing house lcm-22w3 also if im correct i see 12 small i would guess fuses which one is right 1 and is there any way to tell if ones bad?

[cclla]

The LCM-22W3 does not use the same mosfets as the L1975NW does. On that model you will just need to replace the Capacitors to repair the unit. Here is a link to the repair guide for that model.

http://www.ccl-la.com/blog/index.php/category/monitor-repair/westinghouse/

[cptnKirk]

Hello all,
I have followed the steps here and have looked at caps there are 6 side by side that are poped up is this bad news or just replace them all? and MOSFETS as well?
Ok with further looking i see no MOSFETS as in your picture my monitor is westing house lcm-22w3 also if im correct i see 12 small i would guess fuses which one is right 1 and is there any way to tell if ones bad?
ok missed a read i found fuses still need to know what to do if there are not any
mofets? ty.

[cptnKirk]

Hello all,
I have followed the steps here and have looked at caps there are 6 side by side that are poped up is this bad news or just replace them all? and MOSFETS as well?
I would think Radio shack would have these parts?. thank you for your reply.

[ybuba]

link to repair kit is dead. how do i find it and how much is it?
L1975NW.

[ybuba]

i tried the link to buy repair kit. Corporate Computer opens but nothing works.
desperate need for kit. what can i do. please reply asap. thanks

[cclla]

Our ecommerce site was updating and doing maintenance when you tried to order. The link works mow. If you would prefer to order via phone you can call us at 318-447-9040

[cclla]

Here is the updated link.

http://www.ccl-la.com/catalog/product_info.php?cPath=21_35&products_id=28

[jtc10512]

If i need to replace my mosfets, (from what it looks like in the last comment, i dont) where can i go to get them???

[ninjastylemafia]

Sorry dont want to bring dead post back. but I have some problem.

I have almost the same issue as everyone, but I can see very very dim screen. I have tried to use several computers with the monitor but I only get dim screen and nothing.

I've used this method to repair it but I don't see nothing wrong with board or any fuse or caps blown up.

The only thing I can think is that the lights are gone. "(reader) need your thoughts on this"

can any one tell me where I can get the lights from? that is if you (reader) think that the lights are out.

its 19inch Westinghouse L1975nw Monitor.

I hope I've explained enough.

Please reply with feedback.

Thanks.
Ninja

[cobaka]

What if my fuse is completely wiped of the face of the board? Its burnt where the fuse f200 is under one of the capicitors. Is it still possible to fix this?

[phoenix_up]

Any idea what kind of bulb I'd need for this model if my bulb is out?

[jacfar]

I don,t think that there is pulp there is florocent tube light the only way is to check the cerciut mosfet capcitor fuse 12v or 8 in the just check the power two or secondry cercuit good luck

[dualmule2]

i don't seam to any blown capacitors what now may be just change the MOSFET transistors & fuse no clue my monitor stop working during a storm i was using dual monitors i have a digital analog card the digital side still works but analog side seam to be down i test the monitor the one not working which lead me to believe capacitors blown in monitor & analog side of video card is out too what should i do please help