No cab fan but works on bunk heater

lciambotti

Well-Known Member
#1
My 2007 9400I stopped blowing air out the front vents yesterday all of a sudden. I replaced the control panel on the dash with a new one to test, and nothing, however my bunk heater blows just fine. I think I had this problem once before but can't remember how I fixed it. No matter whether on defrost or floor heat, no fan. Any ideas??
Thanks
 

8978

** Commie Express **
Supporter
#2
You need to pull the connection off the fan and put a meter on it. Turn fan on high and see if your reading 12 volts. If you are then the fan is bad.
 

lciambotti

Well-Known Member
#3
there is only one fan I believe and it blows in the bunk. I think there is a rheostat in the same compartment as the fan under the seat. I changed that as well last year. maybe it went bad.
 

GAnthony

Well-Known Member
#4
check with the usual suspects, blown fuse, loose wire, if the resistor in the circuit is bad, usually you get high speed fan only.

given how all trucks take a pounding, that resistor can be broken.