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Discussion Starter #1
So this is my problem, and in doing a search it seems opposite to all the common blower motor problems. Hopefully someone has an idea for me because I'm not sure where to go from here.

Here is the good:
-My HVAC system panel works great, no "book symbols" or other abnormal readings.
-My fan speed switch works great and tells the fan motors what to do as normal
-AC is very cold and heat is hot...just like normal.
-All buttons that direct the air to the different locations work and the air goes where it is supposed to.
-No bits of dash material or any other debris in the squirrel fan
-New pollen filters
-New relays for both fans
-Fuses are all good

Here is the bad and baffling part:
-When I activate the AC system with my desired temperature the fans come on but they do not stay on at the set speed. If I manually adjust the fan speed switch to max for example, the fans will go to max then over the course of the next few minutes, they will slowly run themselves down slower and slower until they don't spin at all. Here is an example of what happened the other day: Get in car and the ext temp is 90 so the int is over 100 probably. Turn the car on and set AC to the LO setting and manually turn the fan speed switch to the highest setting. The fans come on and run on high then they slowly taper off to nothing in about 3 minutes...not nearly long enough to cool the cabin down to the LO temperature setting. Drive the car a couple more miles, then the fans kick on again at full speed but quickly taper off to nothing in the next minute of so.

The problem almost seems like the system thinks it is reaching the desired temperature so it shuts the fans down. However, the cold AC air and AC compressor do not shut down because as i drive, the ambient air still pushes the cold AC air into the cabin...it's just the blasted fans that have a mind of their own.

I have read the numerous posts about fans that stay on the Hi settings...I would like that more than what I have now. My second question is, if the fans cannot get the correct fan speed without a complete and expensive overhaul, can I just add a manual toggle switch of some sort just so I can get them to stay on? When I use the heat of the AC, I really only use the high settings and then direct the air elsewhere or shut the system off if I don't want it...I really don't need multiple fan speeds- I would settle for only the HI setting if possible.


1995-2002 Range Rover P38A
1,851 Posts

From your post I understand that both the fans are shutting down simultaniously. The speed of the fans is directed by the HEAVAC ECU only supplying a signal towards the speed control units inside the blower housings.

The first things you should check are the relays from the fans and your fuse box as this is sending the power towards the fans. If you have problem here with the feed circuits you also might end up with the symptoms you have. And other possibility is the earth path being corroded.

Look up the circuit details in the rave CD and track down all wires and investigate them lubricate connectors with dielectric grease after sparying them with electro cleaner.

To answer your last question it is very simple to get the fans on maximum speed. Just apply +12 VDC supply on the red connector that is otherwise comming from the speed control circuit it is located at the top of the elctromotor and make sure you have the earth connected.

Good luck

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