I can't get a voltmeter on the connector, it's just too small. Here is a complete description of the symptoms my car is experiencing. If I disconnect the monovalve, instant heat, very hot. With the monovalve connected after startup I get a very slight increase in heat eventually. However if I stop the car for a few minutes ( to get diesel for example) when I start back up, much more heat is blowing through the fan! If I continue to drive for another 30 minutes or so, all of a sudden the heat drops back down again! It doesn't matter whether I have the setting on defrost, economy or whatever, the results are the same. Thanks for you help!