P38 Heater vent temp problem

Hi Guys

My first post after lurking for the two months whilst my new (to me) P38 was being fixed by my local LR specialist garage. (many problems, some solved by garage, some not)

Part of the work they did was the dashboard out to renew the heater matrix.
New matrix fitted, and car returned tonight.

Driving home (engine temp on normal) and notice book symbol alight on the display, plus driver side vents blowing cold, and passenger side blowing hot.
A/C is on auto with 21 deg requested on the display. (outside 15deg)
adjusted the temp setting, with no obvious change in temp.

Before the new heater matrix was fitted the system was working, (apart from a leak of course) but without any a/c pressure. System has now been regassed, and comp clutch is working.

Would appreciate if anybody has an idea as to what this could be before I go back to the garage.

Still got other problems with the car, but they can wait for another post.
thanks
Noelmc

Looks as though the blend motors are not moving-could be either electrical or the new heater flaps are tight. Get it back to them straightaway cos blend motors are a pain to do.

thanks irishrover, will bone up on these before I visit the garage tomorrow.

If it is these would it show up on testbook?

Yes the fault will. The garage should have at least recalibrated the blend motors and "Forced" them with the diagnostics to ensure that they were travelling the full range of movement-only takes 5minutes to do-before they handed the car back to you. Check the operation of the distribution flaps in manual mode on the HEVAC to see if that motors working o.k The blown air should come out at the footwell at lowest setting and screen at other end of the flap movement.

Well I've just been out to check the distribution flaps, all working as they should, then noticed that the book symbol wasnt lit.
So tried left side hot, and right side cold, all working as it should, reversed the temps and still OK
Seems problem has disappeared!
Ho Hum!!

Now only EAS and remote locking to sort out, but thats another couple of new threads.

thanks for you help irishrover, what a great forum this is

Glad to be of help.
Thanks for the update. Few people forget, or can't be bothered to let the rest of us know what the outcome was which is frustrating to others who may have the same problem.

looking at replacing my blend motors, without diagnostic kit can you suggest the best way to ensure the motors are sync'd, as I've seen nothing regarding this on other sites.

The motor assemblies have a potentiometer in them which sends a variable voltage which is translated by the HEVAC unit as a position of the output splined shaft-it's a simplified encoder. They have to be calibrated or "Taught" the limits of travel, e.g. flaps fully open and fully closed. This can only be done with either Land Rover software (Testbook), Rovacom or Autologic which independant LR specialists tend to use. Unless they are calibrated, the book symbol will be displayed on the HEVAC unit.