Got my e fans and harness installed in my 03 sss. Used 05 fans and a harness that uses pins 33 and 42. The fans seem to work right but about five minutes after the first start up with them my coolant temp gauge stopped working, just dropped to 160. What could I have done? Anyone else have something similar happen? Please help its hot here and I don't like not having a gauge

 

Your fans will come on by temp so if ur coolant temp sending unit failed then motor wont think its not hot so fans wont come on. Have you drove it around long enough to know its fully warmed up. On my 2000 I had to have my pcm tuned for efans I dont know on 03. If you cant figure out then just rewire to have come on when ignition is on then you wont have to worry

 

Yes I had to tune it also, the fans do cycle on and off, so I guess the sending unit must be good, but why would the gauge not work then?

 

Some vehicles use 2 different senders - one for the gage and one for the PCM - I'm not sure on yours, but it is a possibility you may want to check on...