Apple Performa Plus 14-inch Display power switch issue and workaround

Elemenoh

Active Tinkerer
Oct 18, 2021
384
374
63
Bay Area
This is a mediocre display, but was common to pair with Performa's of its day. It's a Philips C3G9179 shadow mask CRT/Analog board with an Apple badged enclosure and 15-pin connector. It only operates at 640x480.

The display I found worked okay, but its power button quickly broke. It'd press in and make contact but not hold in place.

This display uses a Preh ME5A power switch, which was typical in Commodore and other monitors in the 80s-early 90s. Inside the switch is a little plastic rectangle with a nubbin of plastic that helps the switch lock in place. With age, that nubbin shears off and the switch cannot stay closed.

Unfortunately that switch is not very practical to get a replacement for, especially for this display. There are some new old stock for sale, but the price can be $40 or more with shipping and may just suffer the same failure.

There's a great YouTube video that details how to repair the switch. I followed that method by making some 3D printed parts and doing surgery on the switch. It initially worked but the nub quickly broke again. Since this is a very basic display I don't plan to use much, I ended up just bridging the switch contacts so that it is always on when plugged in. I can use a power strip or inline switch to turn if off/on if need be.

This is the switch. I ultimately bridged the same-colored wires together to have it be always-on.
IMG_8207.jpeg


Here you can see the black rectangle with the nub that sheared off.
IMG_8214.jpeg
 

trag

Tinkerer
Oct 25, 2021
280
133
43
That monitor commonly blew its internal fuse for no real reason. If it hasn't already been replaced, you may need to do so.