Chrysler Repair: T&C Blower wont shut off/only on high speed, blower motor resistor, fan blower

Question
QUESTION: My front fan won't shut off or allow me to control the speed.  It blows air fine but seems to have a mind of it's own.  How sure are you that this would be the Control Block?

ANSWER: Hi Rick,
That is a sign of the fan blower motor resistor block being blown. That is what happens when the resistors blow. Tell me the year and I should be able to tell you where to look for it.
Roland

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QUESTION: It's an '03.  Do I need to be concerned with the air bag in the dash?

I'm pretty handy but haven't worked on car dashes much.

Thanks.

Answer
Hi Rick,
I assume you have the manual temp control unit:
I would look at the resistor block to see if it looks burned out/shorted to ground. The dark green wire from the blower motor goes to the resistor block where there are 6 different paths to ground which are selected by the switch in the control panel. If the switch seems to have no effect on the fan speed (even the off position) then I would suspect the dark green wire is grounded or that the switch in the control is internally shorted to ground. It should only be shorted to ground in the highest speed position, so if the fan can't be shut off either the wire is shorted to ground or the switch itself is shorted to ground which is the black wire going out of the control unit.
If the fan doesn't work on most of the positions, except the high setting then I would suspect the resistor block. You find it by opening the glove box, bending in slightly the sides so that it will drop down, and then you will see the plug/socket of the block. Remove the plug. Remove the screws on either side of the socket and the block will come out.
If you have the ATC unit, then the front blower module or the ATC head unit may be the cause. There is no resistor block with this type of unit.
Roland