My spal fans are turning on at 208 and off at 199. Yes I read the vortex site. Last time this happened I replace the fan switch and that fixed it. So I replaced the switch again and no change. It appears GM discontinued the old switch and the new one has a higher turn on/off temp. My question is does the extender chip determine the fan turn on/off temp? My extender doesn't seem to control the fan. Thanks.