Discovery 4 heater

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hi mate ,

in the meantime the part number is LR016848

OEM £193 plus vat
Genuine £260 plus vat

also some more details , will share as I find things for u

https://topix.landrover.jlrext.com/.../62606/GTR_climatecontrol.pdf?ignore-mobile=1

some details from above

The Timed climate control system provides a comfortable temperature inside the cabin in advance of the driver and passengers entering the vehicle.

The Auxiliary heater is also operated to warm the engine and aid starting in very cold conditions.

NOTES
**** If the Auxiliary heater is used to warm the engine, the cabin will not be warmed.****
 
However this document states

http://topix.landrover.jlrext.com/topix/se...ontrol.pdf

If the external temperature is between +15°C
(59°F) and -20°C (-4°F), then the passengercompartment is heated using the engine's
auxiliary heater. If the external temperature isbelow -20°C (-4°F), the heat is automatically
directed to the engine to assist engine starting

Once the engine has been heated sufficientlyheat will be directed to enable cabin heating
providing battery state of charge is sufficient

will see if I can find a fault checking sheet for that 3 x parking heater valve
 
I have no idea on the d4 but assuming it is much the same as the d3, the only reason the stat housing has a few hoses is the bypass is built into the stat housing itself.
Sounds posh, but all it means is when cold the coolant bypasses the rad to speed up the engine warming up process, then when it gets to temp the stat opens and closes the bypass circtuit sending all the coolant via the rad.
Modern coolant systems are way more complicated than the old stuff.

I reckon Gary was on the right track and it is that 3 way valve.

hi mate

bless u and indeed from what I’m reading that valve does control the cabin heater in some some shape of form , nothing like making the system complicated that’s for sure
 
@Niffty

After some searching just found this on Amazon , will be a right result if it is the correct one, plse see what u think , it’s only £32.00 , alas don’t know what the quality will be like but at least it’s not £200

notes from there advert

Features ---- Heater Control Valve Replacement Part controls the flow of engine coolant through the heater core, which is designed to increase the performance and efficiency of your engine

there’s others on the Amazon website if u put the part number LR016848, but will will check other sites to ensure it’s correct

hope it’s useful to u

Amazon product
 
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Found some wiring for the parking heater , will check to ensure it’s correct

upload_2022-12-25_10-39-14.jpeg
 
Plus would u be so kind to check the following with a multimeter , thks


With both battery leads disconnected from the battery posts

Multimeter set to ohms, ( TP Is just short for test probe from ur multimeter)

TP to pin 6 other TP to pin 14 , read ohms

TP to pin 3 other TP to pin 11, read ohms

plus there is a very basic scanner u could get as that will help a lot, very handy to keep in ur glovebox , it will give u fault codes , live data etc , plus there only £60.00 , just thought it ideal to have one

https://www.autelsale.co.uk/wholesale/autel-ap200-bt-obd2-scanner.html

what multimeter have u got please , hopefully between all of us we can find the fault by going through it step by step

hope all of this is helpful
 
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hopefully it is indeed that 3 x way valve , from what I’ve been reading it does indeed go round the engine first then opens allowing hot water to pass into the cabin heater

not all had that 3 x way valve , it’s basically a park heater and read that it can sometimes work if u tap the solenoid , or the rubber diaphragm inside becomes stuck , maybe if u lift off the solenoid there might be junk in it

of course my only concern is if u fit one and it doesn’t work, have u tried using a multimeter to see if there’s any voltage on it plse , or can the diaphragm be easily removed in the mean time to allow some heat to get into the cabin

also been checking on wiring diagrams as there must be a thermostat to tell it when to open like what @lynall has also mentioned

will read up some more and see what I can find for u , ie what the ohms should be on the thermostat and VDC readings on the solenoid etc , also plse let us know if u have in the mean time any update , thks


I have a new valve coming tomorrow morning. £48 from a local parts place. The local LR dealer want £86 plus vat, i was going to have a go at taking it apart yesterday
but the boss had other ideas.
It looks like its a simple set up thats activated by a motor of some sort that pushes and pulls the valve in and out, if the new one cures the problem i will take the old one apart to see if the internals can be removed and then re-sealed.
Might be helpful info for someone in the future.
 
I have a new valve coming tomorrow morning. £48 from a local parts place. The local LR dealer want £86 plus vat, i was going to have a go at taking it apart yesterday
but the boss had other ideas.
It looks like its a simple set up thats activated by a motor of some sort that pushes and pulls the valve in and out, if the new one cures the problem i will take the old one apart to see if the internals can be removed and then re-sealed.
Might be helpful info for someone in the future.

that’s great it’s not £300 , hopedully it’s that at fault

many thks ref the remote as was just curious , indeed as u also mention won’t work under 1/4 tank

plse let us know how u get on and indeed that would be very informative seeing how they work , fingers crossed for u
 
Afternoon chap
We have semi good news and interesting news, i fitted the new 3 way valve and hey presto i have some warmth in the heater, i also have warm water in the hoses to the matrix, albeit one is warmer than the other.
While this is semi good news, the hoses and blown air are no way in my mind hot where as that cross over pipe with the bleed point in it is very hot.
The interesting bit is, i have warm air blowing on the drivers side but cold on the passenger side. we know the blender motors are working from when it was plugged in so why cold one side and warm the other ?
It might need bleeding again so that might account for the warm and not hot air and hoses.
At least i am moving forward at last.
 
Hi guys, im convinced i posted this earlier but can see it anywhere.

I have fitted a new 3 way valve today and i now have warm water in the heater matrix hoses and some warm air coming in the car,
the strange thing now is the warm air is only on the drivers side, passenger side still blows cold.
Also i do mean warm, the cross over pipe with the bleed point in it is hot, the hoses to the matrix are warm.
Possible air lock in the matrix maybe ????

Why warm air on the drivers side and cold on the passenger side, the blender motors were the first thing our local mobile mechanic checked when he plugged it in and they are all working fine.
I have seen this question ask before on a Facebook thread but ive never seen anyone come up with an answer.
 
Hi guys, im convinced i posted this earlier but can see it anywhere.

I have fitted a new 3 way valve today and i now have warm water in the heater matrix hoses and some warm air coming in the car,
the strange thing now is the warm air is only on the drivers side, passenger side still blows cold.
Also i do mean warm, the cross over pipe with the bleed point in it is hot, the hoses to the matrix are warm.
Possible air lock in the matrix maybe ????

Why warm air on the drivers side and cold on the passenger side, the blender motors were the first thing our local mobile mechanic checked when he plugged it in and they are all working fine.
I have seen this question ask before on a Facebook thread but ive never seen anyone come up with an answer.

Maybe the motors are working just fine, but whatever connects them to the flaps has broken/become detached?
 
Afternoon chap
We have semi good news and interesting news, i fitted the new 3 way valve and hey presto i have some warmth in the heater, i also have warm water in the hoses to the matrix, albeit one is warmer than the other.
While this is semi good news, the hoses and blown air are no way in my mind hot where as that cross over pipe with the bleed point in it is very hot.
The interesting bit is, i have warm air blowing on the drivers side but cold on the passenger side. we know the blender motors are working from when it was plugged in so why cold one side and warm the other ?
It might need bleeding again so that might account for the warm and not hot air and hoses.
At least i am moving forward at last.

hi

that’s great news , so indeed that 3 x way valve was at fault , am so pleased the information helped u , so we’ve made some progress in a manner of fashion

So with one side cold and the other hot will normally signify a blocked matrix or blender motors failed , alas with the matrix the pipes enter and exit on the same end so very difficult to clear , u can get several things , ie, that u plug into ur air compressor / hose pipe

there is a blender motor reset procedure , if u haven’t got it please let us know and can find it for u

Apologises asking, it’s just so we know at this stage but have u done a hard reset yet plse , have ur got ur own diagnosis yet and multimeter as we can then start going through things but alas really need those items in order to progress further into the system

Once again glad the info helped for u to make some progress, bet ur pleased u now have some heat

ps , when u get some spare time would u mind taking that valve apart and sharing some piccies of it please of the internals , etc plse , thks
 
@niffty10

here’s the forced re calibration, kindly provided from @sierrafery earlier link

http://gershon.ucoz.com/LANDROVER/DISCO4/Heating_and_Ventilation-Heating_and_Ventilation.pdf

Forced Calibration: The ATC module can be manually forced to carry out a calibration routine on the stepper motors. This can be carried out by holding down the ECON and recirculation buttons on the ATC module panel while simultaneously switching the ignition on. The ATC module will now carry out a calibration routine on the stepper motors, but will flash the ECON LED rather than the programmed de-frost LED.
 
Evening
I have one of the guns that goes on a hose pipe and compressor, the water shot through the matrix so if there is a block the forced water was passing it.
The guy i had round to look at it plugged his flash computer in and that claimed the motors are working but that dosnt mean they are operating the flaps.

I've been put onto a local garage that specialises in LR he has quoted me for the belts and oil pump, he told me today that he changed a matrix once and
it turned out to be a solenoid for the passenger side motor, he had plugged that car in and it claimed the motor were fine.
Since that mistake he has had 4 more Discovery's in with no heat on the passenger side, 1 was the Matrix, 1 was the motor and 2 were this same solenoid.
Its behind the passenger glove box which is a quite easy job, so I've told him to have a look when he does the belts next week.

I will give that reset a try tomorrow, maybe i will get lucky and it cures the problem.
I will dissect that 3 way valve and get some pictures, hopefully it will help someone else in the future.

Cheers
 
Evening
I have one of the guns that goes on a hose pipe and compressor, the water shot through the matrix so if there is a block the forced water was passing it.
The guy i had round to look at it plugged his flash computer in and that claimed the motors are working but that dosnt mean they are operating the flaps.

I've been put onto a local garage that specialises in LR he has quoted me for the belts and oil pump, he told me today that he changed a matrix once and
it turned out to be a solenoid for the passenger side motor, he had plugged that car in and it claimed the motor were fine.
Since that mistake he has had 4 more Discovery's in with no heat on the passenger side, 1 was the Matrix, 1 was the motor and 2 were this same solenoid.
Its behind the passenger glove box which is a quite easy job, so I've told him to have a look when he does the belts next week.

I will give that reset a try tomorrow, maybe i will get lucky and it cures the problem.
I will dissect that 3 way valve and get some pictures, hopefully it will help someone else in the future.

Cheers

must confess am well pleased the information and help has been useful to u

indeed always the way where it can be multiple errors , awesome regarding the dissection of the 3 x way valve please , also hope it’s not cheeky in asking but with a multimeter would u be so kind to take the Ohms reading of the old and new solenoids please , as we will then have a figure for future reference plse , many thks and again hope u didn’t mind me asking

indeed plse let us know how u get on with the reset

Hope this doesn’t bore u, lol , I use to be a heating engineer for around 30 x years and would often come up against a blocked heater matrix flat plate from boilers, swimming pools, etc

would always fit new ones which allowed me the opportunity to experiment with the old ones , I made up differently designed rigs that cleared out roughly 80% of debris, , however it didn’t work each and every time , but really enjoyed designing the rigs and messing around with them, finally would cut them open and indeed was the same where debris would sit at the opposite end of the pipes

so with many reports of heaters not working I keep thinking of different rigs that could be incorporated temporarily within the system to see if they could be effective of removing as much debris as possible from the heater plates , yeh I know I need to get out more, lol

ref diagnostics if he had a bi directional scanner he should be able to move each and every motor / flap to ensure they worked , then after could check live data to ensure the system was moving each and every one

apologises I’m waffling , lol, just wanted to make sure the information etc has/ is helpful to u
 
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