88 300E Heater problem Fixed!!
A while back I wrote that I had heat coming out of all my vents at all times. Turns out I had a stuck monovalve! Here's how I tested it;
1. Got a volt meter, and tested input voltage going to valve.
The voltage test 12 volts completely cold, and alternated between 6 and 12 until completely open where it registered about .6.
2. Created a jumper that went directly from the battery to the valve. With 12 true volts, it was still open.
Replaced the valve and all was good. I just replaced it today, so I will follow up in a few days with a status!
Thanks for all the help!
Help me fix my mercedes!