Late 90s AOC 7Elra PC crt monitor not working

[pac.attack76]

I wanted to use this with my old win 98 setup especially since it's white and a crt. It turns on but I've never seen a menu or anything. There's no static discharge. The led lights come on and immediately goes to standby. I would imagine the degaussing button should work but nope. Nothing. Any ideas? Stock images below show the same model as mine.

[pac.attack76]

Ok, it's working now but looks like the blue is missing. I move it around and it turned red once. Checked the pins, moved around a bit but no change.

[MadMan]

On VGA each color is on a different pin. Quite possible the pins in the plug are damaged or corroded, or the cable itself is bad. Play with the cable and plug while it's on and displaying something. See if it affects the picture.

[pac.attack76]

Originally Posted by MadMan

On VGA each color is on a different pin. Quite possible the pins in the plug are damaged or corroded, or the cable itself is bad. Play with the cable and plug while it's on and displaying something. See if it affects the picture.

Yeah I did that. It turned red once. Moving the plug is the only thing that affects it. I checked the cable all the way to the back of the monitor and nothing. I'm wondering if it's one pin that's responsible for blue and which one

[MIPS]

The heavily shielded cables by that point were so stiff that if you flexed the cables too much by their ends you could damage the cable internally by pulling it apart.
Normally when I get cables that lose colors when flexed I replace them but if it's a monitor where you don't have a VGA connector right on the back your choices are to cut off the old VGA connector, solder in a new one and hope the break was on that end or completely replace the cable up to its connector inside the monitor.

[pac.attack76]

Originally Posted by MIPS

The heavily shielded cables by that point were so stiff that if you flexed the cables too much by their ends you could damage the cable internally by pulling it apart.
Normally when I get cables that lose colors when flexed I replace them but if it's a monitor where you don't have a VGA connector right on the back your choices are to cut off the old VGA connector, solder in a new one and hope the break was on that end or completely replace the cable up to its connector inside the monitor.

If I don't get anywhere with it the way it is, I might change it out

[MIPS]

I have a pair of really long 50 foot VGA cables that came out of a classroom ceiling that lost a color or two just by handling them too rough when taking them out. Two really common failures is the heavy pink tint or a light yellow tint.

[pac.attack76]

Tried again today during post screen. All text is yellow. Moving around at end of plug, I managed to make it turn red several times and green once and back to yellow.

[Electronic M]

One way you could check the cables is to open the back find the R, G, and B coax lines and jumper the center conductors together with something like 50 ohm resistors. If the picture becomes monochrome and you have decent light from all colors then it's the cable. You could also do continuity checks on the cable. On the video coax lines if you have a capacitance meter that reads down into the pF range you can figure out where the break is on the coax by measuring capacitance on both ends (make sure both ends are unplugged from everything else) and using the ratio of capacitances to figure out how far down the line the break is.