on my way to work this morning, my 92 240s' heat didnt work, but i didnt think anything of it. when i got to work and let it cool down i checked to make sure it was top full of coolant, which it was, and just left it alone.
i made a post earlier about my temp gauge not working, and a few people said to replace or to fix the compensation board by crossing the first and third poles, i was gonna give it a shot but couldnt figure out how to get theodometer panel out (specifically the screws on the left side). the temp gauge will randomly decide when to work, and i'm not really sure if the tempature it occasionally shows is right.
i bring that up because when i got home from work i noticed the tempgauge had jumped itself into the red, something i've never seen it do. i wouldnt think anything of it because the car sounded normal and that gauge is messed up anyways, but it was odd that the heat stopped working at the same time also. i shut the car off and opened the hoodto look for any blatant signs of overheating, mainly steam, and there was none. any ideas?

 

Bypass the temp. comp. board and check the thermostat.