So I did a little more diagnosing and i think you may be correct when it comes to being one of the stepper motors. FYI, I changed the motor closet to the floor on the drivers side. I know its the temperature motor because when i had it out i turned the temp. **** and saw that it moved whenever i did that. With regards to the rear heating, all of the third row and ceiling vents in the rear blow hot.

What i did notice was when i have the heat on max, the drivers side is not only cooler but the air that is moved through the vents is considerably less. When i change the temperature on the drivers side all the way to cool, the temperature does go down; however, the air that is pushed through these vents is also increased to (what feels like) the max. When you turn the temperature back to hot, the air moving through the vent decreases to maybe 2/3 less and is luke warm.
So it would seem like its one of the motors more difficult to get too...?

I was able to change the one stepper motor without taking the dash apart. It wasn't easy, i just fanagled the plastic covers. I would consider myself a moderate wrencher as i just changed the suspension air compressor, front diff and transfer case within the past few months. So I might just have to rip it all apart as you suggest and just change all of the stepper motors...

 

The two lower motors are I think possible to change out without total dash removal; in fact I think the drivers side lower one, (the one you have already done), is harder to do than the passenger side lower stepper motor.

That was really valuable info that you were able to watch the motor cycle when physically removed but I presume still electrically connected.

I may be that re the passenger side stepper, that you could first remove the electrical connector and then attach it to your removed motor from the drivers side and see if it cycles as you would expect. It probably will, and if so, that suggests the computer signals are OK.

Then it would be a matter of removing the existing motor and seeing how it cycles. Hopefully, it does not. Probably you could then install the previously remove motor as I think both stepper motors are the same part number however a second new one would make more sense.

And yes, if you have to tear everything apart, then you may as well purchase the two upper motors as well.

Page 10 or 11 of the attached shows the rear heating system ducts and vents. It sounds like at least the rear system is operating OK so that pretty much suggests there are no air locks in the cooling system and that the problem at the front is control related.

DISCO3.CO.UK Photo Gallery - Heater Air Conditioner System/LR3 Air Conditioner Drain Tubes behind centre console

http://www.disco3.co.uk/gallery/albu..._Operation.pdf

 

One other thought I had related to the systems voltages.

Now that the question seems to relate to the operation of the stepper motors, consideration has to be given to the voltages available to the control systems.

I presume that when you are cycling the motors, the engine is running. As such, there is probably at least 12 volts and sufficient amps available to the computers.

It may be however that it would be a good idea to first charge up the vehicle starting battery for a few hours so that when all off, you have a healthy 12+ volts - say 12.2 or perhaps a bit more to suggest the battery state of charge is pretty good.

I say this as these control systems tend to have a cut off voltage of perhaps about 11.7 VDC. This means the computers, even though they most often run on 5 VDC, will shut down in the middle of an operation.

The problem is that the computers start up and work OK for awhile and then in the middle of events, shut down, and that is when confusion starts.

I expect the motors run on a nominal 12 volts but being stepper motors are probably more fussy than one might expect and also that they get their instructions from 5 VDC computers.

It is just that when one starts to get into the control systems, then the battery state of charge and condition of the charging system starts to matter.

 

Ok, so just did ALOT of work and still have the problem.
I replaced the stepper motors on the drivers side (upper and lower).
Still nothing, heat is blowing very cold on drivers side and super hot on the passenger side.
I think I'm going to try to clean out the heater core to see if that does anything.
I know that in my D1, i had to do this every year or so.
I will keep you updated.
Thanks,

 

I am sorry to hear that.

I presume then that 3 of the 4 stepper motors have be changed out now; the only one not replaced is the one on the passenger side at the top that is near impossible to get at.

I guess we have to conclude that all the stepper motors are working OK and the problem is water circulation. That I do find difficult to accept however.

I assume you did that stepper motor self-test procedure where the motors in theory are cycled by holding the ECON and RECIRC buttons while turning the ignition switch to the ON position and of course nothing improves.

One thing I would do is to drive around a bit before I was to pull the heater core - sometimes it takes awhile for trouble codes to work their way out of the system.

If you had one of those Faultmate like code clearing devices, then the procedure would be to read codes prior to the fix, and then clear all codes prior to the fix, make the repair, then read codes again and clear again.

Incidentally I noted you said the air this time was blowing very cold and in a previous post, (11-07-2014 07:14), luke warm was the term. Perhaps the weather is just colder now I suppose but could something be upside down so to speak - that is operating in reverse? In other words, try setting the left side control ***** to full cold and see if anything changes however I suppose you have done that many time over.

In the absence of any code clearing device, then one has to wait for the codes to clear and sometimes the repaired item then works if you are lucky.

You do not sound lucky however - this is just no fun.

 

Thanks for the reply,
I did do the ECON and RECIRC procedure, probably about 5 or 6 times. Still nothing happened. I am slightly frustrated but this is not really too big of a deal.
I will figure it out. I believe the difference in the temperature may be due to it being really cold out now and in the mid 50-60s when i first started working on this.
I will clean out the heater core by just shooting water through it to see if that helps.
I am still not totally convinced that it the core itself at this time vs. the work to change the core. If this doesn't work i may just have the codes read at the dealer to see what they come up with being that i don't have anything but a basic code reader.

I will keep the board updated.

 

Hi,

I just read your comments on the heater problems. Last week my car was in the shop and had several things done including replacing the thermostat and housing, water pump..and 4x4 service. After picking it up, I now have the heater problem as described in the posts...driver side cold - passenger hot. I have not done your tests yet, but wondering if you think any of the work done could have caused my problem.

 

My view is whatever caused the problem cannot be blamed on the fix it techs. I would like to say otherwise but having unrelated systems quit after fixing stuff is a norm with the LR3.

Right now my Clock on the Dash is showing just blanks rather than the time; the clock on the radio is still OK. Last week, the Clock on the Dash was working prior to me taking my 3 in for new again, inner tie rod ends, a wheel alignment, new belts and two new belt tensioners plus one idler pulley and also a flush of the power steering system.

I am now waiting to see if the clock comes back by itself but it probably will not.

The last time the clock quit, I later started getting red warning lights related to the air suspension and the antilock brakes. The problem turned out to be a broken conductor located in the left front wheel wheel well feeding the wheel speed sensor on the right rear wheel. As such, I am wondering if some wire is in the process of breaking somewhere, and the loss of the clock is a first hint.

When I do decide to attempt to resolve the problem, my first action will just be to clear all the trouble codes with my Blackbox Nanocom Evolution.

The odds are that will not work, but it is easy to do - clean hands and all.

My second fix attempt will be to do a hard reset and I hope that will resolve the concern. My thinking is that when replacing the tensioners, the fixers probably had to unplug the electroviscous fan system cable connectors and that may have disturbed the tranquility of some system.

In the past I have had the "no radio sound" problem when a new alternator was installed - disconnecting the battery I guess - and the fix was a hard reset.

If the hard reset does not work, then I may try a software reinstall but that is not without its risks also. Regards, I do not put the blame on the fixers - the 3's systems are so interrelated, shutdowns routinely happen.

The link below is to my album related to the HVAC systems, if you do not have it. One of the files within is a 14 page pdf related to how the rear system is supposed to work. With that system, a first fix attempt is just to swap the rear fan relay in the engine fuse box with one of the other similar relays. Removing a relay is a pliers to grab on "softly" kind of task while pulling steadily upwards gently, but with real effort - kind of an art thing.

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


Below are the Hard Reset Instructions

Hard Reset Instructions

In brief, to start the hard reset process, open the hood but close all doors and let your 3 go to sleep - no radio display etc and no key in the ignition. This will take a couple of minutes and do not open any doors until the reset is completed. (I find that it is often a good idea to have the driver’s door window rolled down and the key in my pocket whenever fooling about the vehicle.)

Also when I play with a car battery, I remove any rings I have from my fingers, also my watch.

Disconnect the ground battery terminal from the main starting battery.
Disconnect the positive battery terminal from the main starting battery.

The reason for this order is if a wrench or loose battery cable ends grounds to the body, no arcing or other bad things happen.

(I assume that you only have one battery in your 3. If not, disconnect the others as well and leave them disconnected until after all is done.)

Connect the negative cable end to the positive cable end. (NOT the battery.) To do this, you will need a short length, (a foot or so), of light gauge, (14 to 18 gauge AWG, insulated stranded copper), wire to span between the battery cable ends as there is not enough slack in the positive and negative battery cables for the ends to touch each other.

Hold all together for about a minute or more, (at least two minutes), as you are discharging memory modules within the engine computer and elsewhere. Then it is suggested you then just let all sit disconnected for say ten minutes, (minimum five minutes), prior to commencing to put the battery cable ends back on the battery posts per the following order.

Reattach positive terminal to the main starting battery positive post.
Reattach negative terminal to the main starting battery negative post.

Start engine and hopefully the rear heater fan works.
Reset the time on the radio - note that the station presets are still there as not everything is erased. Nothing much else needs resetting either.
You can also now connect up the other batteries if you have a multiple battery setup.

This is a link to a thread in disco3 re the hard reset procedure. http://bit.ly/14WXXR1

DISCO3.CO.UK - View topic - Hard Reset

This is a link to a thread on Disco3Club re the hard reset procedure.
Disco3Club The Discovery 3 and 4 Owners Club ? Login

 

I realize this is an old thread, but am wondering if anyone has had work done on the air blend doors. I have a similar problem on a 2010 LR2, but with a slight difference. Which is, sometimes the left side blows cold air, but at other times, it does blow hot air as it should. It seems to happen after I've used the A/C, but not always. My local dealer says the heater is "recalibrating", but it doesn't switch from cold to warm unless I turn the engine off and restart. There is also a soft metallic type "woo-woo, woo-woo" sound while it's blowing cold. It's not a real "woo", but that's the best I can use to describe it.

 

See my post #25 on page 3. It is the reset procedure for the LR3 but I think you have similar buttons that you could press.

I doubt anything bad will happen if you attempt the reset. It may be just that your air doors are a bit mixed up at times. The reset is supposed to get the logic of the door management back to factory setting or what we would regard as normal.

Other than that, I am not familiar with the LR2 heating system. I expect it is some sort of Volvo/Ford setup, hence you may have to troll some Volvo or Freelander forums and do a search under heater or HVAC or air doors.

Below is a link to the Freelander LR2 forums here on Land Rover Forums. There is probably something in there as most of these problems are not new; someone else has already suffered thru it.

LR2 - Land Rover Forums - Land Rover Enthusiast Forum