While the rear fan is working properly, the front fan is only coming on randomly. According to the fan display on the dash, the controller is telling the fan to run at high speed(it was 0 out this morning) but nothing is happening. I tried to override it on all speeds including high with no results. I also tried cycling power to the system with again no results.
Is there a relay that needs wiggling or am I looking at a new fan?
mfahey
01-19-2008, 03:48 PM
In using the search function, it appears that there is a good chance that the power module for the fan may be the problem. However, I wasn't sure if there was also a relay in the system.
mfahey
01-31-2008, 10:53 AM
The problem appears to be the fan motor itself. I picked a time when the fan wasn't working and found that the controller was putting out 12v. This confirmed my suspicion in that the problem only shows up in cold weather and since electronics such as the controller like cold temperatures, my thought was the bearings on the motor.
If someone could tell me what's involved in changing the motor, I'd appreciate it.
Rick99
01-31-2008, 01:35 PM
The problem appears to be the fan motor itself. I picked a time when the fan wasn't working and found that the controller was putting out 12v. This confirmed my suspicion in that the problem only shows up in cold weather and since electronics such as the controller like cold temperatures, my thought was the bearings on the motor.
If someone could tell me what's involved in changing the motor, I'd appreciate it.
Never had to do it, but if I remember correctly it requires removing the dash to get access to the HVAC box, same as changing the evaporator or heater core (which you may want to do at the same time if you do this). This is a very big project-- about 10 hours book time.
Double check the fan by hooking 12v directly to it and see what happens, if it still doesn't work or goes in and out, you've verified the problem. Also, before you condemn the fan, make sure you are measuring for voltage at the controller output. There is a constant 12v feed to the controller.
mfahey
01-31-2008, 04:12 PM
That doesn't sound too encouraging as far as taking the dash apart. When I tested the controller, I only tested what I took to be the hot wire going to the fan. There are two different connectors on the controller, one of which I assumed was the signal connector coming from the AC controller and the other was the hot and ground going to the fan. You have given me reason to go back out and recheck my assumptions.
mfahey
02-06-2008, 05:37 PM
Well, I broke down and got a subscription to alldata after the dealer said it would be at least $600 labor and even my usual mechanic said it would be $450. You do have to "roll" the dash to the rear. Unfortunately, alldata says to roll it but the procedure they show is to totally remove the dash. This means that many of the steps are unnecessary to get the dash to move far enough to access the HVAC system. Too bad they didn't differentiate between instrument panel removal/replacement and moving it enough to get at the HVAC system.
However, there seems to be one last unseen screw holding the lower intake air housing to the upper. If anyone has done this job and can share how to get the lower housing off without breaking it, I'd appreciate it. Alldata doesn't show the screw locations, just that there are 2 of them. I've looked from the top with the dash rolled to the rear and I've looked underneath and just can't seem to see what I need to disconnect.
XDGT03
02-06-2008, 11:15 PM
I changed my evaporator this spring so I have the whole friggen thing apart. I am not sure what you are asking. Can you post a pic of what you are talking about? Do you mean the whole black HVAC housing? It is bolted to the firewall with three nuts that you have to remove from the engine compartment with triple jointed arms and hands and a lot of patience.
Here is my thread with pics
http://www.dodgetalk.com/forums/showthread.php?t=160692&highlight=evaporator
mfahey
02-07-2008, 01:04 PM
I finally got the lower housing off this morning. All of the work involved in disconnecting the instrument panel and rolling it to the rear was for one lousy screw that is up by the firewall next to the AC lines coming in from the engine compartment. I actually never saw the screw but by running my hand towards the firewall, I was able to locate it. One hour later and I had the screw out.
May the Chrysler engineers who designed this spend the rest of their afterlife trying to find and remove this one screw. Clearly, the way the van must have been assembled is that the HVAC system went in first, then the fully assembled pillar to pillar instrument panel and finally the windshield.
