P38A HEVAC

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
You should be able to see the distribution gears via the instrument cluster hole ? Check the two black gears are correctly aligned with the grey gear. The attached picture shows them in the screen vent only position.

The black gear on left of picture controls the floor vents, and the right black gear opens & shuts the face & screen.

Those two are attached to square rods which have the distribution flaps on them. If someone has had the gears off at some point, it's possible the square rod is not properly seated, hence the gear doesn't move the flaps.

1715521774621.png
 
Many thanks, I am wondering though if I could have dislodged something while re-assembling after doing the Orings, it was working before I stripped everything (or I think it was.....)
 
When you did the O rings did you strip the whole dash out or make the special hole for the long screwdriver and cut the duct?
If you cut the duct it's not a big job to get access to the hvac motors again. You might be able to see all the hvac gears moving as they should even with the ducting still in place by removing the cluster, knee panel and the left hand cluster support metal bracket.
 
I cheated, someone way back in the past had done the short cut so I have gone in that way again. I actually replaced the distribution motor 4 or 5 years ago when I found it had been chopped.
 
I am looking a various pictures of the HEVAC trying to see what I may have dislodged, the car is out for a service so I cannot physically see the gubbins
 
cornishboater said:
I am looking a various pictures of the HEVAC trying to see what I may have dislodged, the car is out for a service so I cannot physically see the gubbins
Click to expand...
What pictures do you need ? I have a complete heater box on the bench ready for my Blue P38 when I take the dash out, so I can take pictures later today when I'm home.
 
Many thanks and much appreciated, I am just psyching myself up for when the car comes back from the service.......
I have found some pics on this site and google but none really show where I may have disconnected something, so basically the distribution motor area if you could. Can you confirm that the blend motors are the same as the distribution one, I have 2 brand new ones just in case, Keith has said they are but because there is a divided opinion I thought I had better make sure. Having said all of that I am presuming the motor works as it doesn't create a fault during calibration and forcing various % of open, it just seems to be missing something mechanical.
 
cornishboater said:
Many thanks and much appreciated, I am just psyching myself up for when the car comes back from the service.......
I have found some pics on this site and google but none really show where I may have disconnected something, so basically the distribution motor area if you could. Can you confirm that the blend motors are the same as the distribution one, I have 2 brand new ones just in case, Keith has said they are but because there is a divided opinion I thought I had better make sure. Having said all of that I am presuming the motor works as it doesn't create a fault during calibration and forcing various % of open, it just seems to be missing something mechanical.
Click to expand...
I wonder if you missed one of the screws holding the motor to the box and it's 'pivoting' a bit?
I remember it was a bit difficult to line up one screw on each motor.
When you get round to it, it's quite easy to see the gears on the box going round as they should, a mirror and torch is useful to see the one nearest the cabin, they are black and small. I've no idea which gear does which flap but if you move the big grey (or is it white, I forget) 'thing' you can see if they are free and all rotating as they should(motor off first of course) if that's OK then take the motor apart, check for stripped gears, if that's OK, enlign the little arrows, reassemble , and refit back to the box. Try working it again with nano while watching the gears.
If you need to do work on the motor, search my recent posts on hvac and there is a pic on there showing how to get loads of slack on the cable by stripping it down and poking it through a hole behind the main light switch.
 
Thanks, I didn't actually touch the motor on this bit of surgery, I replaced this motor years back. I will check however when I get the back later today. I am wondering if when trying to get the ducting back in I inadvertently dislodged something as it was working fine prior to this. I guess I will find out soon!!!
 
pwood999 said:
Keith is correct the Blend & Distribution motors are all identical. The only difference is what pins they connect to on the HEVAC ECU and the colour ident on the cables !


View attachment 316984 View attachment 316985
Click to expand...
The recirculation ones are different though, incase someone reading this orders a recirculation one like my friend did when his rh blend packed up!
Recirculation ones only have 2 wires not 5 but the motors inside ARE the same which saved my friends ass.
 
Flossie said:
The recirculation ones are different though, incase someone reading this orders a recirculation one like my friend did when his rh blend packed up!
Recirculation ones only have 2 wires not 5 but the motors inside ARE the same which saved my friends ass.
Click to expand...
And for those that don't know, the Recirculation motors are attached to the fans . . . . . not heater box. Rumour is they are also almost impossible to access !
 
Right, I am now extremely confused, I have just picked the car up from having the service done, this had nothing at all to do with the HEVAC just oils and brake checks etc. I jump in and drive away, no book fault on the HEVAC and the face vent is blowing cold air in my face. So I switched to manual mode and selected floor which happened immediately and then face level with the same effect. It wouldn't blow a wig off but then it never did, don't know if that is normal but it has always been that way. Switch to auto and bingo, up and down obviously nothing has fallen off. This bloody thing has a mind of its own.

Many, many thanks for the info and assistance, very much appreciated. I am now going to leave well alone, including the recirc which I never used anyway, the only thing I would like to do is to unbind the one that is shut but as the rumour says (and I have looked) these are a near impossibility to do anything with as the access to the bolts is up against the body. If LR had designed them with the bolts the other way it would have at least given us half a chance!!!!
 
cornishboater said:
Right, I am now extremely confused, I have just picked the car up from having the service done, this had nothing at all to do with the HEVAC just oils and brake checks etc. I jump in and drive away, no book fault on the HEVAC and the face vent is blowing cold air in my face. So I switched to manual mode and selected floor which happened immediately and then face level with the same effect. It wouldn't blow a wig off but then it never did, don't know if that is normal but it has always been that way. Switch to auto and bingo, up and down obviously nothing has fallen off. This bloody thing has a mind of its own.

Many, many thanks for the info and assistance, very much appreciated. I am now going to leave well alone, including the recirc which I never used anyway, the only thing I would like to do is to unbind the one that is shut but as the rumour says (and I have looked) these are a near impossibility to do anything with as the access to the bolts is up against the body. If LR had designed them with the bolts the other way it would have at least given us half a chance!!!!
Click to expand...
I wish mine would do the same!
 
You must log in or register to reply here.

Similar threads

A
P38 2000 4.6 Thor vogue RHD HVAC issue
Replies
4
Views
494
alex230718
A
pwood999
P38A HEVAC Blend Motor Testing
Replies
9
Views
845
Datatek
Datatek
P38 guy
Blend motors delete/ motorcycle choke cable
Replies
11
Views
628
Hicap phill
H
Mark Piercy
P38A Hevac.....🤬
2 3
Replies
51
Views
4K
Datatek
Datatek
I
Change Hevac Controler
2 3
Replies
49
Views
3K
Mark Piercy
Mark Piercy
Back
Top