I just split the coolant system and added a Heat exchanger. I thought why not change the fluid, wish I would have not done it now, let me explain. I received my Heat exchanger took everything apart drained all the fluid after splitting the system and everything buttoned up and the pump wired to run all the time. Filled up both systems let the IC pump run to bleed itself once all air was out started car and the message was there turned car off restarted no message let car idle about 10 mins with heat on to help get all remaining air out. ck'd level again all was well. So now after 100 miles the message comes back on only after 3 starts or so then I have to turn it off then start again and its gone. Temp is good and message has never came on while driving, only on start up cold and hot. I'm lost on this issue Has anyone had this problem?