svenology's latest activity

so to test, if I put a 12Ohm load instead of teh relay's solenoid, I should get no book symbol... or... just a 12W light bulb....

adding on... wrong load on the relay vs. compressor would also explain why I still get a service book symbol, when bridging... meaning, now I have NO load... not even the relay... so old school HEVAC not happy.... Correct thinking? When R3 is...

burning 50Watts seems the wrong approach... I'll check the HEVAC first. I might even have another unit from my old 2001 in one of my many bins from moving to back to Europe... ended up ordering an already rebuilt unit when the screen was acting...

in https://www.landyzone.co.uk/land-rover/air-con-woes-nanacom.312452/ @boycie says https://www.landyzone.co.uk/land-rover/air-con-woes-nanacom.312452/post-3951061 That seems to confirm suspicions now of a wrong/older HEVAC front end in a new car

the relay I swapped already... so that seems to be just fine. But explain to me this... how does the HEVAC "see" the current the AC clutch draws? Isn't the clutch engaged by the relay and the relay's solenoid current drawn is the only thing that...

Followed your advice... when I jumper the pins 30 & 5 I have a working A/C circuit. Clutch engages. Fans run every now and then... I get cold air. AC clutch also seems to be cycling... i.e. turn off for a few seconds every now and then. Climate...

No

I'm fairly sure one of my HEVAC is the early version, mainly because I had clutch gap issues causing intermittent operation. Both of them in my P38's and my spare all have heated seat buttons. Only real way to tell is to take the unit out &...

and on the new setup with the relay, the HEVAC would only measure the resistance/load to the relay, no longer to the compressor clutch as it used to... correct?

from @wammers on https://www.landyzone.co.uk/land-rover/p38-hevac-unit-versions.228929/post-2624184 "It is the dual pressure switch that controls the compressor." So maybe I do have a bad switch or bad relay. My HEVAC controller is the newer...

I never replaced the unit... BUT now that this drive transistor comes into play, I wonder if that is the issue... That would in my mind make the most sense currently for the book only showing when HEVAC is trying to use the AC. And the AC clutch...

this is the switch I am thinking... I do not ever hear the fans going on when the AC is allowed to go... but presumably just like my other cars, that wouldn't happen until the system is active for a while. I do get the fans to go on for engine...

I will give that a look. what I am missing in this diagram is the second switch that is for the fans... or is this a newer version, which would explain why my fans switch on when the engine gets very hot.... which seems to not be mentioned...

Remove relay #3 and jumper pins 30 & 5 on the drawing. The relay pin numbers will not actually be the same but a DVM will tell you which pins are which. If the aircon runs with the jumper, you are left with 3 main possibilities, faulty relay...

I've had mine on and off alone quite a few times. Tricky part getting it back on is getting the sides to slot back into place. Mine is just black plastic coated and not colour coded though. Don't know if yours is any more fragile but mine's...

Car has been recharged at a professional shop and the pressure was all good.. also no leaks... but also there... the AC did not cycle... so the million dollar question... who determines the cycling and via what sensors? Clearly the HVAC codes for...

+1 on first job is to sort the LH Blend motor. Remeber the book symbol comes on for any faults within the HEVAC system. Probably worth getting a set of AC gauges & check the pressures. Even if you never re-gas yourself, at least you then...

I have had 3 failed motors on my last RR and other than the adjustments not working or the left and the right getting different temps of air, when they should be the same, the AC always worked... i lived in California... and a no AC car is as bad...

honestly i think the car has basically no rust for a a Range Rover... the clips all seem visible and moveable. If the bumper wasn't painted I would have already taken it off a long time ago... but this one is pristine and has a clear coat etc...

Front bumpers tend to be okay, rear one often comes off and won’t go back on. Some manage fine you could be a lucky one. Best have a good mooch underneath with the EAS right up before tempting fate if you feel there may be crumbliness in there...

i know this sounds super "princess"... but my bumper is gloss color matched to the body paint... In your estimation, if I put down a blanket... what's the chance I still get it damaged due to warp, falling etc?? also... off is one question like...

okay... latest update. Code in the HEVAC (says left blend motor failed auto tune) doesn't clear with my RSW EASv4 tool... no way it resets faster than 30 seconds it takes to reread codes again. but the book doesn't relate to it... book is off if...

Often had the bumper off on my own. Undo the clips at either side, undo the two bolts, push down in the centre to disengage it and then pull it towards you and it just slides out. Get ready at the end as it comes free and the ends drop towards...

The not having any code is frustrating… But as the dual pressure switch is the only other dependency of the compressor and I had the AC professionally evacuated and recharged, I don’t know where else to look. Who votes for just pulling the bumper...

Yes. But book only comes on when the ac is being tasked. Otherwise no. Also won’t stay once the ignition is cycled. Always same behavior. Going cold to hot (ambient air) works without issues. So to my knowledge the blend motor uses the same...

I waited for my eas cable from RSW hoping it would allow me to get a code… but no dice. The only code in the HEVAC which doesn’t even clear is left blend flap failed auto calibration… but it seems to work just fine when I play through the...

That’s why I am thinking dual pressure switch. I even have the part sitting on my desk… just have never pulled a bumper… and have no helper. Anybody done a solo bumper removal? Mine is pristine and color matched with the car. So don’t want to get...

You are effectively by-passing a gas pressure problem. Have you tried running in manual mode?

Just to reiterate. My compressor clutch is fine. Using a jumper to engage the clutch manually gives me nice cold air. So the system works in terms of charge and the compressor doing what it needs to do.

yes. the EAS unlock has HEVAC connectivity and can read, clear faults and also has all kinds of calibration and test functions for the blower motors and blend flaps... I had hoped it would give me the code for why the book symbol appears when...