Should I change the ';air temperature control module'; or the fan motor first to fix my car's climate control?

Ok, so here's the deal. The fan used to stay on all the time (I couldn't shut it off, even if the console was ';off';), but now it won't come on. So nothing comes out, but... only when the car isn't moving. If the car is moving, especially on the highway, cold air comes out when the a/c is on and hot air comes out when the heat is on. So... I'm not a mechanic, but if the appropriate air comes out when the car is moving but the fan just doesn't come on, I'm a little concerned that my mechanic is just trying to get more money out of me, even though he's been a very reliable mechanic in the past. Oh, not sure if it makes any difference, it's a '99 Chrysler 300M Please help. Thanks.Should I change the ';air temperature control module'; or the fan motor first to fix my car's climate control?
The fan motor is extremely easy to test and certainly not necessary to replace it just to see if it's the problem.


It's also easy to test for voltage at this motor with the control set at different fan speeds.


This is a concern that should be easy to diagnose and swapping out parts to find the cause is ridiculous - and expensive.Should I change the ';air temperature control module'; or the fan motor first to fix my car's climate control?
i would check that the fuse and wiring on blower moter. it could be short to power at one time now blower doesnt work at all,check for open in wiring . check the blower by hot wiring it to the battery if blower does not work the blower moter is shot .yes check your air temp control.it could have cable or vacuum off of it check that before taking temp control off
under the passenger side of the dash, you will see the blower motor, a circular metal thing. you'll have a few wires going into it. remove the connector and hook up a test lamp to the big wires. turn the fan on high and see if the test lamp illuminates. if it does, then the blower motor is inop and you should replace it. if it does not, than it's either a wiring issue or an controller issue. have a mechanic fix it for you. the only thing you'll be able to do is a blower motor