Fluke 75 III multimeter repair


Fluke multitester is not your ordinary tester on the market. They are highly reputable when it comes to maintenance equipment and tools. But even they is not vulnerable to harsh environment and they too fail like this one. LCD is no longer functional most probable due to moisture and humidity to where it was stored. 

Liquid Crystal Display has a tendency to suffer failure such as this for their composition consisting of layer of polarizing film that when placed properly will those digit be displayed at the correct viewing angle.

To fix it, of course you need to dismantle it from the mainboard. Gather your needed parts such as

1. polarizing film- you can choose either 0 degree up to 90 degree type of polarizer, 

2. cleaning agent preferred 99% iso alcohol

3. Sharp bladed for old film removal

4. piece of  cloth that do not leave residue preferred those sunglasses cleaning cloth

5. a bit of patience and common sense about LCD. what is it, let me tell you about it.

LCD FIX common mistake when repairing it. They forgot NOT to wipe the LCD contact part to which it has a carbon traces for the rubber contact onto the board. So when they wipe it so does the carbon contact and after assembling it and test. broke display is all they have and unfortunately it cannot be undone instead of repairing it. They destroy it even further and no longer useful. There is no other way really but to find a replacement LCD if there was any.

Inspect the LCD. does it need both film to be replaced or just one. you can tell if both are wrinkled already or not. But on the case of this Fluke Multitester, needs both. Scrape the old film using your sharp blade carefully until the adhesive is gone. Thoroughly clean the glass with your ISO and cloth. 

Trick on the film. cut the desired size for the LCD and place it first at the back stick it using its own adhesive.






Assemble the unit back, and still without the front film. just put the UNCUT film on the top and just rotate it until the correct viewing angle of the display is shown on the LCD and it should end like this.

Unfortunately I forgot to shoot a photo doing it but just visualize what I am talking about.

Now the FLUKE75III is useful again. Unit is not cheap but repair yes.


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