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-   -   99 WJ Blower fan runs constantly (http://www.jeepgarage.org/f203/99-wj-blower-fan-runs-constantly-17087.html)

Rottweiler123 01-05-2011 06:59 PM

99 WJ Blower fan runs constantly
 
The heater blower fan on my 99 WJ runs all the time so I have to pull the fuse to get it to quit. Anybody know whats causing this? :)

Frango100 01-06-2011 12:05 PM

Re: 99 WJ Blower fan runs constantly
 
Depending on which system you have ( Automatic Zone Control or manual control), it is probably the blower motor controller or resistor block respectively.

Rottweiler123 01-06-2011 01:00 PM

Re: 99 WJ Blower fan runs constantly
 
Quote:

Originally Posted by Frango100 (Post 329413)
Depending on which system you have ( Automatic Zone Control or manual control), it is probably the blower motor controller or resistor block respectively.

Thank you for your reply. I have the AZC setup and having looked under the glove compartment it looks as though the control box has been replaced at some time or another. I shall get it tested and see if this replacement is faulty. :thumbsup:

Frango100 01-06-2011 07:39 PM

Re: 99 WJ Blower fan runs constantly
 
You could try to find error codes yourself with the AZC system: You most probably get 03 or 04, which has to do with the Fan control. You could clear the memory by disconnecting the car battery for a minute or so and check if the fan works ok.

ENTERING THE AZC SELF-DIAGNOSTIC MODE
To enter the AZC self-diagnostic mode, perform the
following:
(1) Depress the a/c and recirc buttons at the same
time and hold. Rotate the left temperature control
knob clockwise (CW) one detent.
(2) If you continue to keep the a/c and recirc buttons
depressed, the AZC control module will perform
a Segment Test of the Vacuum Fluorescent (VF) display.
In the Segment Test you should see all of the
display segments illuminate as long as both buttons
are held. If a display segment fails to illuminate, the
vacuum fluorescent display is faulty and the a/c
heater control must be replaced.
(3) After viewing the Segment Test, release the
A/C and Recirc buttons and the display will clear
momentarily.
If a 0 is displayed, then no faults
are set in the system.
Should there be any faults,
either
currentor historical, all fault codes will be
displayed in ascending numerical sequence (note no
effort is made to display fault codes in chronological
order). Each fault code is displayed for one second
before the next code is displayed. Once all fault codes
have been displayed, the system will then repeat the
fault code numbers. This will continue until the left
side set temperature control is moved at least one
detent position in the CW direction or the ignition is

turned
OFF

When you are in the self diagnostic mode , you can also enter into the actuator test mode. Turn the left temp knob so that pointer number 02 is shown (that one is for the Fan), and pressing the A/C or Recirc button will put the system into the actuator test mode. By turning the RH temp knob, you should be able to control the fan speed. If this works, then you know that the Fan controller is ok and that the problem is probably somewhere in the panel/switch.

Robert G Beals 12-12-2011 06:21 PM

Re: 99 WJ Blower fan runs constantly
 
Thanks, I did not know about the ACTUATOR TEST MODE when using the AZC self-diagnostic mode.

Gus9890 12-15-2011 12:45 AM

Re: 99 WJ Blower fan runs constantly
 
Also could be a relay


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