P38 heater problems.

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
S

SteveMin

Member
Posts
18
Location
Ayrshire Scotland
Hi, I have a 1996 P38 and have heater problems. The passenger side is fine temp can be set up or down but the driver side is cold only , which is a bit of a pain when it is cold and raining. Any ideas ?
 
Hi,

I have the same issue, thought its the passangers sides thatys cold. Althought I can change the flow of cold air from floor to vets to screen. Having discussed this with a number of poeple they say it is more likley to be the HVAC playing up. Thoughts anyone.
 
Dancernbc said:
Hi,

I have the same issue, thought its the passangers sides thatys cold. Althought I can change the flow of cold air from floor to vets to screen. Having discussed this with a number of poeple they say it is more likley to be the HVAC playing up. Thoughts anyone.
Click to expand...

Hook it up to Faultmate or similar, and see

- if there are any fault codes reported
- use the live data readout to check that blend motors are working and temp sensors are returning sensible values

Only then will you be able to really start diagnosing the problem

Cheers,

Jerry
 
Hmmmm mine is same problem but other way round..
I can control and change drivers side temp no problem, but the passenger is always hot, no change at all when a/c used or temp control up or down.
Think a/c is not actually working either but could need re-gas.

Could be a little warm in the summer !

Stu
 
It stopped raining for 20 mins so went and had a play :p
Actually do get control off temp on the passenger side for a while, got it hot, then cold, hot cold for 5 mins then it went hot and stayed hot... turned off and on again, had cntrol again... I am thinking maybe a sticky blender due to lack of use.... fingers are crossed that I won't be smashing the dash up !
But also means I can set to cold for the summer if I have too and will at least have minimal control of temp ... happy days.

Stu
 
Same issue with my drivers side one, noticed mine was stuck on cold just after the summer. Took it apart using the method on rangerovers.net to drill a hole in the dash to get access to the ducting screw, worked a treat. Cutting the ducting out after that bit took two hours.

Glad I did it though because the matrix went after that, further surgery to the dash frame to get that out.

I moved the blend motor to hot for the winter, now it too hot so it needs sorting.

I am hoping the motor is ok, because you can buy potentimeters for them, and overhaul them I am told. I am going to have a go with mine, I have sent too much lately on it to not.
 
I have been playing some more and have now noticed there is no set pattern to the fault other than igntion off and on again re sets control for a short while.
Both blend motors now seem to be playing up after a few minutes, I thinking its not the blend motors at fault at all but something that controls the signal to them ?
Any idea on what that is ? I have read that the dash control unit itself can be faulty ...

Cheers,

Stu
 
Camo said:
I have been playing some more and have now noticed there is no set pattern to the fault other than igntion off and on again re sets control for a short while.
Both blend motors now seem to be playing up after a few minutes, I thinking its not the blend motors at fault at all but something that controls the signal to them ?
Any idea on what that is ? I have read that the dash control unit itself can be faulty ...

Cheers,

Stu
Click to expand...

I would say it's the HEVAC unit itself at fault.:( The only way to tell will be to monitor the outputs that drive the blend motors. Put the system on to Manual and see if it's the same as a duff sensor may also cause the same thing to happen. You need to check it out with diagnostics.
 
Last edited:
Faultmate ?
There's my problem, I have no idea what that is, where to get it or even if I can get it...
I assume its either a program for your laptop or only available at a Landrover dealers ?
Sorry, I am used to older cars !

Stu
 
Camo said:
Faultmate ?
There's my problem, I have no idea what that is, where to get it or even if I can get it...
I assume its either a program for your laptop or only available at a Landrover dealers ?
Sorry, I am used to older cars !

Stu
Click to expand...

Faultmate is professional diagnostic kit from www.blackbox-solutions.com covers every system on the P38, allows you to force the blend motors for example or look at live engine data as well as reading and clearing faults.
A cheaper unit that does not need a laptop, but still covers all systems, is the Nanocom Evo from the same company:D
 
Managed to sort mine with the nanocom evo. I had blend motor short circuit fault. Changed blend motor and now its fine. Nanocom evo recalibrated the blend flaps, you can then get each one individually to move by forcing them to a percentage of their movement to prove they are working and giving feedback to the hevac unit. Nice.
 
You must log in or register to reply here.

Similar threads

P38 guy
Bent chassis
Replies
13
Views
622
P38 guy
P38 guy
pete12345
P38A Heater
3 4 5
Replies
83
Views
6K
pete12345
pete12345
R
Discovery 2 heater issue
Replies
1
Views
167
sierrafery
sierrafery
P38 guy
Blend motors delete/ motorcycle choke cable
Replies
11
Views
438
Hicap phill
H
JT_spark
P38 DSE Auto intermittent lack of power after vehicle has been hot
Replies
8
Views
510
brianp38dse
brianp38dse
Back
Top