I have read somewhere that the early version HEVAC control heads that have the outdoor ambient air temp sensor located in the fresh air intake plenum versus the later units which had that sensor located in the front grill area are somehow different? Maybe how the temperature offset is calculated?
Can anyone verify this?

Reviving an old topic here. My sunroof mechanism is probably worn out, but here is my problem. I have adjusted the glass as far as it will go upwards, but it still sits about 3 to 4 mm low from the roof panel. This results in the glass being lifted and water dumping down my neck and seats when going through the far too powerful drying blowers of automatic car washes.
The "Home" location" described before is determined by a microswitch located inside the gearbox and is activated by a cam on the driven gear. You are also correct about stall current when opening and closing. That is also part of the window/sunroof anti-trap safety system.
I don't know how many revolutions the driven gear makes during a full open/close cycle, but I suspect the switch is ignored by the BECM if an open/close command has been initiated.
The motor can be resynchronized to the sunroof if you set the sunroof where you want it, remove the motor/gearbox, unplug the multi connector, cycle the ignition to clear the sunroof memory. Then using a multimeter set to ohms check the switch wire to gearbox ground, turn the gearbox manually with a hex wrench until the switch just.......And that's where my memory fails. Sorry. I have done this successfully several years ago on my other P38, but can't find the info right now. I'll figure it out again if need be and fill in the blank.

I've had two P38's with a ticking noise from the engine that I couldn't locate or identify.
The first was a 4.0 petrol. It let me know what the issue was when number 8 cylinder liner slipped, allowing the top piston ring to expand and ripping the piston, wrist pin and connecting rod into pieces.
The second P38 I'm still driving with a similar noise, It's the Callaway edition 163,000 miles and I stand on the pedal and blow down the Hi-Way at 97 MPH passing cars and trucks. Hasn't come apart yet?
These noises are near impossible for me to define even with an engine stethoscope, my feeling is the way sound is transmitted in a cast aluminum vs. a cast iron block. I've also had a 3.8 and a 4.6 Bosch (THOR) motor with no noise at all save for a little ticking in the rockers.
No help here, just my experience.

Thank you for the info.
I've had many things sent over from the UK, Germany and even a couple other countries in Europe.
eBay works worldwide for me and even the phone if I have all the correct digits and country code.
If the price is right, and they ship, I'll take it.
I've even had a help with re-shipping a radiator from another well known member on this site.
Still grateful. That radiator works a charm.

Thanks for the replies guys. I'm not ruling out the electrics by any means (found plenty wrong there) but crossed lines is going to be my first check.
So-called mechanics have worked on this that shouldn't be qualified to repair a lawn mower.
We now return you to your normally scheduled broadcasting.

This probably won't be helpful, but I'm grappling with an ABS issue that I have come to suspect stems from a previous owner having castrated my Callaway P38, and it is currently sitting on hideous coil springs.
Sometimes I inevitably have to make a sharp turn into the near lane of traffic from the apron of a narrow parking exit. This causes my right rear tear tire to become suspended in air for a brief moment. (jumping the curb) Every time that happens, the ABS locks down hard, and I mean hard. Even at 2 to 3 MPH (under acceleration), I nearly have to pull my teeth out of the steering wheel. Very annoying.
So finding a way to desensitize or the energy and time to put it back on proper air springs would be very nice.

It would be great to find a source for these. I'm missing a couple myself, and they can be a source of water condensate intrusion.
With these missing, moist air can enter, and the vent tube can't do its job.

Makes sense. I have cleaned it as you say through the grill, but never removed it to do so. It's getting far too cold for me to be working on vehicles, so this will probably be on hold until April or so, along with the Discovery and the awful noise from the front end of the P38.
I would still like to source a used replacement, so I can have it refurbished and ready to install.

I have tried turning the temperature settings for both sides up to 84 degrees F, but that seems to have no effect on air distribution, only cabin temperature. I will continue manually selecting the floor outlets. That works.

Thought I'd post my findings in case anyone's interested.
The heater matrix pipe sensor is as spot on as one can expect, as is the outdoor air temp sensor.
The cabin aspirator temp sensor however is reading about 18 degrees F above actual. I thought I had a spare, but either I don't or I can't find it (not unlikely) so I'm hunting for a used one without any luck so far.
I will need to check the value of the thermistor and replace it. By the printing, of course, the value won't do me any good. This may or may not explain why the thing is so insistent on blowing warm air out of the fascia vents instead of the floor. I really hate cold feet. My other P38 behaved similarly, though, so it may just be the way it's programmed.

Thanks, David, for the reminder. I just checked, and it looks like I need the NCOM26 Right-hand cable.
I recall them having them, but I had forgotten, and I was unsure at the time if it would work with the dual vehicle cable I have. Being an extension and according to what it says on the website, they will work with all cables.

Thanks for the tips. Yes I have a Nanocom and I will plug it in later this week after it stops raining, and it warms back up into the 50s once more.
It's a bit awkward plugging in with my bendy problems and being located at the front of the passenger foot well. I really need to make a short extension with a 90 degree OBDII connector on it and leave it attached.

I have CRC contact cleaner and Deoxit contact cleaner/enhancer. I will use that to see if that helps.

Not only that, but I've also just discovered that I have no blades left on the interior air temperature sensor. I do have a couple of 10 mm micro fans that I picked up a while back so I'll try rigging one of those up temporarily on the front of the grill to push air through it.

I seem to recall that there is an engine coolant temperature sensor attached to one of the heater matrix pipes that would prevent the blower motors from ramping up to speed until the engine temperature was at least luke warm.

Mine is blowing at or near high speed out of the heater ducts at 10 °C or a little less maybe.

Am I being forgetful again, or just crazy? The schematics in RAVE clearly point out the connector and pin for the sensor.

And why do instrument lamps seem to go out when it's too cold to hold a screwdriver and the plastic is brittle? (that's a rhetorical question. I know the answer).

I checked the boots today, and they seem to be in good shape. No splits, tears or cracks. I felt inside the bellows as much as I could, no problems there either.
I did come across a bit of up and down thrust play in one direction of the front prop shaft U joint. It needs attention but should be good for a while the way I drive.

I know the previous owner had very bad mechanics working on it. Very shoddy work. It could be that the boots were bad and then replaced without replacing the CVC joints or attempting to clean and regrease them. Unknown.

I'll check the diffs and transfer box tomorrow as it's been a while and then pull it back out from the front of the drive for the road. I can switch off between it and the Dodge depending on the weather and road conditions. I may even get the Discovery figured out at some point yet.

Thanks for all the fast replies. I feel better about it now. Like I said, this is the first one I've ever had begin to make noise.
You may very well be right about the damaged boot (gaiter). I have checked them, but it's been a while.
I don't drive it hard. Most people pass me all the time on city roads but not so much on the Highway. It's very happy running along at 80 to 90 mph.
Mine is automatic being a US model and I always set the park brake before taking my foot off the main brake, it doesn't roll that way.
I'll just have to find bigger parking spaces.

Hello to all. I find myself in a pickle. The Rangy Has a CVC joint, front left I think that has started clattering while making turns at low speed. The Disco driver door latch still is not letting me out of the vehicle, and I'm on my second replacement from Rimmer Bros. so it's still out of service. Winter is approaching, I don't have time to replace the CVC joints and have already parked the Rangy for the winter, which leaves me with a midsized, overpowered dodge pickup that is a nightmare to drive on slick streets.

Here is the question, how long do any of you think the CVC joints may hold up before shelling out completely? Might they get me through the winter?

I've honesty never had a CVC joint go bad on any of my rovers in all these years, so I have no Idea what to expect. It's an 99 HSE Callaway in case you didn't read my siggy.

Thanks

Found it! Whoda' thunk to look all the way at the back of the "Electronic Suspension" section when it in fact has absolutely nothing at all to do with whether the suspension is electronically controlled air or mechanical springs.
Thank you. I have it, and it's pretty much as expected. I'll have to look into the tool mentioned for installing the oil seal or if like may a socket the right size will do the trick nicely.
Just a side note, the reference number is 60.25.01.

Gilbert nailed it. It happens when I'm turning, usually close to steering lock position while maneuvering. Not really when changing from reverse to forward gear.
I will take the time to check prop shafts and ball joints as best I can anyway while under there of course.
I will look in that section again. Thank you for the pointer. I thought I had looked there, but I think a lot of things these days and forget a lot of things as well.

Seems to me, they used to call these something a bit different. Like CVC joints or something. No matter.
I have something clunking in the front when backing out of parking spaces and maneuvering at low speeds in parking lots.
I've been very lucky I guess that I've never had to change or really get near a CV joint on any of my Rovers to date, but I have a feeling that is going to change.
So with all my versions of RAVE disappearing or failing to open, and the one left that does work makes absolutely no mention whatsoever of CV joints, Hubs or even ball joints, I'm hoping for an insight as to what to expect or look out for. Any special tools needed?
I'm planning to replace with Bearmech parts, but I may have to order them directly from Bearmech, no one seems to be carrying them.

Gil...allowing for my total inability to not see the forest for the trees at times given, I still need to say that the link provided "http://rangerovers.pub/static/rave.zip" just takes me to the main index page for the site. Is this link no longer working?

I have had a few different versions of RAVE myself and all have either mysteriously disappeared (read operator error) or stopped functioning altogether.
This last bit I don't understand at all but the PDFs simply don't load anymore.
I need a fresh copy.

The door card is off. I never re-installed it before testing the door closer. The structure of the door on a Disco is a little more difficult to work with than a P38. The latch sits well inside the structure and the window frame is in the way. As a matter of fact it has to be removed to change the latch and that can't be done if the door is closed.
Gil, I have had the rear door off. Had to cut through the check strap because I couldn't get the pin out.
There is a fair amount of difference between Discos and P38's in design. Things tend to be thinner and more compact to maximize interior space while keeping the exterior a bit smaller.
The front door exterior skin when closed almost completely covers the latch strike. I was able to cut through the outer bar of the strike at the expense of some door edge damage but the inner bar is too close to B pillar to cut with a reciprocating saw and there is no room to get anything else in to that spot.

Thanks everybody for your replies and willingness to help. At this point it is parked for the winter and there it will sit until warmer weather returns.
Also, this really is off-topic and not the place to talk about Discovery's. So again, thank you but I think it best if I drop this issue here.