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Discussion Starter #1
Hello all... I have a strange issue with my '99 RR (186,000 miles - yahoo!)...

When using the a/c, it works great for a while... then without warning the book symbol appears and the fan speed automatically drops to about half the output. It will run like this for about 30 minutes (longer at certain times) then it'll drop to almost nothing coming out of the vents (side vents and top middle vents).

BUT... there's a ton of air (not really cold) coming out from where my left knee sits. The air seems to be escaping from the right corner of the dash down by my knee. There's not a vent down there... it's where the HVAC tubing connects from the left blower motor.

About this time... I get a ton of condensation on the top middle vents... water droplets appear all over the vents.

Any idea? I'm guessing the right blower motor gets too warm and cuts off. Then the left blower motor does something strange and a blend door closes.

One note, I can manually adjust where the air comes out... ie. I can use the footwell vents, face vents, and defrost vents by pushing the buttons.

I would really appreciate any guidance you can provide. I've searched RAVE and can't find anything...
 

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1995-2002 Range Rover P38A
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Hmmmm ..... the fan speed could be a blower failing. When it happens, open the glove box and listen if the fan is spinning (or, remove the kick panel below the steering wheel and do the same). When 1 fan fails the other becomes almost ineffective.

If you remove the kick panel you will see that the duct from the fan is quite loose (at least, it is on mine) and would allow air to escape quite easily.

If it is a motor failing, you can get a used replacement or fit new carbon brushes.

HTH a bit.
 

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I'm wondering if the temperature sensor in the evaporater core is kaput. The hevac ecu doesn't know when to allow the evaporator to defrost, and it becomes blocked with ice, and forces the air out of any joint before the evaporator core. Any air that does get through would be very wet, and maybe it's condensing on the vents.

Mine's got the opposite probelm. I think the termperature sensor on the intake pipe of the heater core is gone. In the morning when I start it up, the book symbol pops up in about 7 minutes, and then the fans come on - but only when it's heating.
 

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1995-2002 Range Rover MkIII / L322
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Check and see if both blowers are running. If only one runs due to fuse box or other issues the evaporator will most likely ice up and as it thaws out the water may get blown to the vents before it drips out.
 

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Discussion Starter #5
THanks for the tips... where is the post on replacing the carbon brushes in the blower motors? I can't seem to find it...
 

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Discussion Starter #6
okay, I've removed the glove box and the knee plate on the driver's side. When the error message (book!) appears, the fans slow down a lot, but both of them are still running. I've noticed the flap behind the screen on the intake closes when this happens. If I press it open a little with my finger, more and more air comes out of the vents. So I'm guessing whatever tells the flaps to close is the problem.

Any guidance on this? I really appreciate your help!!

Thanks
 

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1995-2002 Range Rover P38A
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okay, I've removed the glove box and the knee plate on the driver's side. When the error message (book!) appears, the fans slow down a lot, but both of them are still running. I've noticed the flap behind the screen on the intake closes when this happens. If I press it open a little with my finger, more and more air comes out of the vents. So I'm guessing whatever tells the flaps to close is the problem.

Any guidance on this? I really appreciate your help!!

Thanks
See if the pollen filters are blocked.
 

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LEGACY VENDOR
1995-2002 Range Rover P38A
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Relays 6/7 in the fuse box? Heating up and causing bad connections? If they're warm, crispy, brown on the bottom, or if there's any sign of wear on the fuse box under the relays... then they can cause big problems with blower motors..

plus all of the above advice :D

Marty
 

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1995-2002 Range Rover P38A
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Hi

If one of the fans does not run the air from the other fan will take the easy path out through the not running fan towards the inlet. This means the underside of the dash if the recirculation mode is active or the pollen filter if it is on fresh air mode. So if both fans are turning does not mean that they are both running. One can be running and the other one is just driven by the air that is passing through.
Most of the time irregular operation of the fans can be traced back to relay, fuse box or connector problems. In some cases it can be worn brushes but this is most of the time starting with symptoms that the fan not wanting to start running after it has come to a complete stop and after tapping it or driving over a bump it will suddenly start.

Regards

Jos
 

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Hello!
In my opinion first of all , the vents must be checked with the A/C. off. (to eliminate the A/C defects like frozen eveap.etc)
Start the engine , disable the A/C,and put the vents on maximal position!
You have the 4 connector on bouth vents.Please fit a multimeter on the big wires (more then 12V must be there).
You cann also see the vents via the pollen filters door,and apreciate her speed.
Try after a few minutes to verify the 2 vent. relays on the engine fuse box,if there is not soo hot.
If the relays exccessive warm, change them and inspect the fuse box relay's terminals.
If all OK. the next step is to verify the "air distribution motor", or the blend-motor.
Dany
 
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