 the faster the blower will run so what we can do is in the shop we get our voltmeter out and we put it on the pulse width setting after we've verified all those other powers and we check and see do we have a signal coming in if we don't we either have a broken wire between that module and the control and the dash or we have a bad dash control the dash controls are known to be problematic sometimes even if you replace it you may have had a bad one you put another one in