Have an 05 LR3 that my AC had been working fine. Just a couple days ago the ac just stopped working. I get back in the car a couple hours later and the ac works fine. This has happened several times now and it is making it difficult to track down the problem. I reset the hevac by pressing Econ and Recirculate buttons it flashes 10 times. Anyone know what code that it if any?

I am able to change between the different exit points in the cabin. The heater works fine. I also noticed what looks to be condensation dripping behind the driver rear wheel. Is this condensation normal or not condensation at all?

 

Every year I have to put about a pound of the R134A "Freon" back into the AC system. It takes about 900 grams total so a pound is about half and it seems my system leaks out about half of that each year - kind of normal it seems.

I also put that UV dye into the recharge so that if I should get to looking for the leak, it will be easier to find.

In other words, when was the last time you charged up the system?

I assume you have the rear heater/AC as I do. The condensation behind the rear left side tyre is water off the AC. Normally you do not see either the water from the front or rear as the rear water drips onto the top of the muffler heat shield and evaporates and the front water, onto the middle skid plate.

In the link below, note the file where perhaps one of the two hoses that direct the front AC water thru the floor boards self disconnect and then the water soaks into the carpet.

DISCO3.CO.UK Photo Gallery - Heater Air Conditioner System

 

Thank you for your reply. I broke down and took the LR to an AC shop. They found a leak and corrected it. They said it was a pound low just as you had mentioned. Thanks.

 

Yes, a pound low always seems to be the response - a billing thing I think.

I appreciate you giving us your update; it is nice to get feed back as to the results of a query.

 

Back again. Yesterday was another hot day 98 degrees. I drive to the store with cold ac when I get back in to come home. No more cold air. So today I take it back they find no other leaks and freon level good. They now tell me to update software for the AC system for $250, and if that doesn't work it must be a bad compressor. He pulled up two TSB for the AC.

First LA412-001 Poor Heating and Ventilation Performance
Second SSM67637 Updated AC Compressor

What are your thoughts?

 

001 as below relates to uneven cabin cooling rather than no cooling so it is not the solution. The other one, SSM 67637, I cannot find, however it appears to relate to a new compressor install.

In other words, if the shop was installing a new compressor, perhaps the update if that is what it is would be a good idea. It may be kind of the same thing as re the suspension compressor upgrade, the new AMK unit needs an update as it replaces the old Hitachi air suspension compressor.

In other words, if you find out just what the 67637 update is about, please let us know.

I assume you are talking to a LR dealer as not many others have the ability to upload new software, and in some cases, not even a dealer.

Here is the info on the 001 bulletin.


No: LA-412-001
Issue: 1
Date: 14 Mar 2006

SECTION: 412-01
Heating and Ventilation System Performance

AFFECTED VEHICLE RANGE:
Land Rover LR3 (LA)
VIN: 5A000360 to 6A380334

CONDITION SUMMARY:
POOR HEATING AND VENTILATION PERFORMANCE
A customer may report a concern that the heating and ventilation system performance is poor, with possibly one or more of the following symptoms:
^The upper torso area is significantly cooler than the lower body and feet area.
^The cabin area near the doors is cooler than in the center area of the cabin.
^The cabin is colder than the set temperature.
Cause:
The control module software may not be providing adequate air distribution under all conditions.

Action:
Should a customer express concern regarding the above, refer to the Repair Procedure detailed in this bulletin to update the control module software.

TOOLS:
LRCD13...................WDS CD Disc 13 or later
WARRANTY:
NOTE :
Repair procedures are under constant review, and therefore times are subject to change; those quoted here must be taken as guidance only. Always refer to DDW to obtain the latest repair time.


In other words, 001 is not the solution but then your dealer should know that? Perhaps after the AC gets working again, then perhaps the update would be a good idea, but not before

Replacing AC compressors is not unusual so that may be the solution - it is simple anyway.

 

I agree with you 100% about the update 001 is not the solution. You are correct the other is an updated compressor. I'll get you all the info when I get home. The shop specializes in LR/BMW/JAG etc. it makes me nervous though since they want to do the flash update that really doesn't have my symptoms, and 250 just to flash. They won't do anything else until that is done either.

The ac is working again and has been all day. I would do the ac compressor but not sure about the freon and charging the system. I am pretty good with a wrench but never worked on ac units.

Do ac compressors work intermittently when they start to fail or do they just quit working?

 

Regarding the intermittent operation, perhaps the problem is not the compressor but the fan or worse, the control system?

I think that you have the rear AC as well. If you put its settings on manual, perhaps you can get the rear to work properly? I note you said the front heater is OK which suggests the front fan is also OK but I still wonder.

The link below has a number of files within that explains the theory of the operation of the AC and heating systems, both front and rear. It may be of help.

I do not know much about AC either, particularly these Denso systems. From what I have read, the AC compressor usually seizes and the frangible "pulley" connection shears as it should. It sounds like your compressor may still be working and the problem is more control related - much tougher to figure out.

Maybe that is why the shop wants to do some sort of software update first - as an experiment.

Also consider switching rear heater fan relay R10 with front heater fan relay R16, both in the engine compartment fuse box just as a no cost experiment.

DISCO3.CO.UK Photo Gallery - Heater Air Conditioner System

 

Thanks for the suggestion. Still no luck. Today was a hot one over 100 and just stopped again when I returned from the store. Is there any way to test with a multi meter if the pressure switch is bad? The back and front both blow hot when it is not working even in manual mode.

 

Hopefully there is an independent shop in your area that does Denso AC systems. I somehow doubt software is the problem and the dealer, (I presume), suggesting software as first fix bothers me.

All the Japanese vehicles use Denso AC so there should be someone who speaks Denso. It could just be the pressure switch, but as to how to test it, again I do not know. I expect it is something simple as it seems it works and then it gets tired and quits.

Intermittent is harder to fix than dead.

Since both front and rear both quit at the same time, then it is something common to both. As such, we are probably back to what tells the AC compressor to make "cold".