[khurmit]

Does anybody know the physical location of part number 4 on the attached diagram?

I have been hunting around in the engine bay for a while now. Its looks as though it should be connected to the lower pipe coming out from the bulkhead (which heads down the passenger side towards the radiator) and should be located somewhere near/under the power steering fluid reservoir, but in reality that pipe only leads to the radiator/gearbox oil heat exchanger, and not the strange looking contraption you can half see at the bottom of the picture (not sure what it is as not numbered).

Any one know of any other pipes that come out from the bulkhead?

To give a bit of background, my cabin heater isn't working and BMW say it's due to a faulty Heater Control Valve. I want to remove and test prior to ordering the part.

[khurmit]

Thinking about this, the diagram I attached previously is for the "Independent heating water valves".

My car is a UK spec 335i Auto, so I am thinking it doesn't have an "Independent Heating/Auxilliary heating" system, as that's some thing special that people living in colder climates (Canada, Russia etc.) have?

The next attachment shows the "contraption" which could just about be seen at the bottom of the previous image - it seems to be the Auxilliary Heating unit, which in the attached diagram is heated by burning fuel and even has it's own exhaust/muffler - kind of backing up my point that I don't have Independent\Auxiliary Heating.

Can anyone clarify what is going on here????? Basically:

a) Do I have a Changeover Valve in my UK 335i Auto with dual zone climate control
b) If so, where the hell is it!?

[doughboy]

go to www.realoam.com and get the proper diagram for your model.

BTW no you don't have aux heating.

[khurmit]

Realoem diagrams are the same - these are better quality.

[doughboy]

Yes, both your diagrams are from parts groups labelled 'Independant Heating' or 'Auxilliary Heating', you don't have Independant Heating, so none of them apply to your car.

If you look here, at the basic (non aux heating) heater water circuit, there are no valves. http://www.realoem.com/bmw/showparts...97&hg=64&fg=18

You don't have a changeover valve. This seems logical in any plumbing scenario, as you have nothing to 'changeover' to or from. Could the very common Dealer Illness known as 'talking out of their arse'.


Also, the heater rad has no valves either: http://www.realoem.com/bmw/showparts...74&hg=64&fg=15

Although, the second fiche could be different for your model/year as that one is for my 2009 LCI variant.


In my (limted) experience of car heating, the water inside heater rads flow all the time, it's only the air flaps that control the heat into the cabin.

Ask BMW to give you the part number of the mystery 'valve', type it in to realoem and see where it is!

[khurmit]

I concur with your diagnosis! Exactly what I thought, but wanted a second opinion before I call BMW Berry Heathrow and challenge them - they want me to buy the £110 changeover valve (#64126951815 as per the RealOEM/BMWFans diagrams) and I have to pay up front and wait 5-10 days for backorder from BMW AG.

Only to be told "oops sorry sir your car doesn't need this part. We'll have to re-investigate"

I never fail to be impressed by the SAs shittyness in BMW garages. They know & do sweet F.A.

[doughboy]

That's clever of them, considering Auxilliary Heating has never been available in the UK on E9x!!!

Can't you challenge them about it?

Run the engine a little (not too hot to avoid burnt hands) if you can get a hand on both the heater-rad feed and return pipes, and they are both hot, then its a sure thing that he rad is hot too, and it sound like an air-flow flap problem.

[khurmit]

Yep already tried that - both pipes leading to the bulkhead running along the passenger side of the engine bay get hot (to the same temp).

Called BMW and challenged the parts guy - even he is adamant that the part is correct for my vehicle (which RealOEM also lists as a part for my vehicle when I enter my chasis number).

So, looks like there's no arguing with stupidity! I will order the part & pay upfront, wait 10 working days for delivery, then book the car in, leave it with them and wait for the phone call to tell me they were wrong. Then all the fun of trying to get a refund from them and to get them to properly diagnose the car.

OR we are completely wrong and my amateur mechanic skills are way inadequate for the complexities of modern BMWs.

I do hope we are proved wrong, cos I want my cabin heating back ASAP! Thanks for your help Doughboy - I'll update this when I know the outcome.

[doughboy]

Entering your VIN on realoem doesn't confirm the spec of your vehicle, it just drills down to the model and production date to save you doing it yourself.

So it doesn't know if you do or don't have aux heating (or any other option for that matter). You have to know that yourself.

I'll be interested to see if they can find somewhere to fit it. Maybe they'll fix it a different way and just keep the bit you bought?

[khurmit]

LOL exactly what I thought - was planning on asking them to keep the "failed" valve for my inspection when I return to collect the car after the work has been done.

Wouldn't surprise me if they keep a bin of spares and just dig out a random valve just to keep me quiet.

[eg9_dc2]

i have similar enquiries.....

did you put your car on a gt1 and run some diagnostics?

http://blog.bavauto.com/12282/bmw-an...w-to-diagnose/

i changed my thermostat still no luck it was a waste of money really i had a feeling it wouldnt be that but i had fingers crossed.lol.

[khurmit]

Hi yeah I hooked it up to my laptop running DIS (an older version of the BMW dealer diagnostic system) but there are no codes etc, and the temp readouts from the temp sensors are all normal (i.e. not reporting erroneously high temps).

When I change settings on the dashboard I can observe these changes reported in DIS (although I am sceptical whether that is just telling me that the IHKA recognises the request, and not that the flaps in the heater module are actually moving, although I can hear flap noises when I do this).

Thanks for the link - is there a way to test if my thermostat is working correctly? I always assumed it would have thrown a fault code that I would have picked up by now.

And also it is strange that the Heater Control Valve is mentioned in your link - I am so sure my car doesn't have this valve - I have had the bottom engine cover and top engine cover/micro-filter panel off & followed all the heater/coolant pipes in the engine and that part is not to be seen anywhere (and definitely isn't where it should be, which is in the engine bay, hooked into the passenger side front wheel arch, just where the heater/coolant lines run).

I'm gonna try to bleed the coolant tonight - I had a strange experience this weekend when I was changing brake wear sensors whilst waiting for the car to heat up to do some more DIS tests - had the passenger side of the car jacked up and the cabin heater was definitely working when I jumped in the car to reset the service indicators - as soon as I dropped the car back to the floor and went for a drive, it was cold again. WEIRD Makes me think there might be air in the system and the car being on a tilt removed the airlock (but I didn't bleed the system at this point so the air may have gone back in)

[eg9_dc2]

thermostat is electrical so it should probably throw a code.....

do you know how to activate the water pump for bleeding? ie holding pedal down for 10 secs etc?

i had my car on the dis version where you can test if the flaps are opening.....it sends the signal and reports back....i guess the flap could still be physically broken who knows lol...

i think its the mixer flap that decides the temp isnt it?

ive read in some bleeding methods they insist you have the car tilted up from the front whilst bleeding? try parking your car on a very steep hill and then try the heaters/bleeding/adding water etc....

also yeah i guess our cars dont have a change over valve.....however our heater controls literally act like a manual change over valve...instructing the mixer flap on how much heat to let using a temp sensor? (id guess that anyway)

im gonna be checking fuses/relays shortly....

[khurmit]

Yep - I will be bleeding manually 1st by running engine & warming up, then tilting car various ways to get the air into the coolant expansion tank, then releasing the air (hopefully) using bleed screw.

Then I'll do the electrical pump method (press start without foot on brake, temp settings to 28 deg C both sides, fan setting to 1 bar, hold down accelerator for 10 secs, listen to waterpump doing it's thing for 12 mins. Then bleed using expansion tank screw, top-up and repeat).

You are correct about the flaps - there are 2 mixer flaps in the Dual Climate control system:

http://tis.spaghetticoder.org/s/view.pl?1/10/97/32

See the "Inputs/outputs for IHKA" diagram (parts 14 & 15), and the "Overview of the IHKA components" diagram (parts 4 & 10). I assume one regulates passenger side temp, the other driver side, but I would be surprised if they were causing my issue, as they'd both need to have failed at the same time?

Also I am hoping it's nothing to do with the flaps/heater core cos I can't be arsed getting into that in this weather! Wish I had a heated garage :-(

On the up side, I have found a thread where the guy concludes there is no heater control valve:

http://www.e90post.com/forums/showth...=504111&page=2

On the down side, he had to replace his core DIY style. Don't fancy it as the DIY seems V involved.

[eg9_dc2]

you could get a local garage to try a flush/reverse flush for you? its only 2 hoses and pretty easy....

they normally have 1 of those air guns/wires and can put water/pressure through the hoses...

worth trying as its cheap...i dont see why it shouldnt work as long as you have fluid coming out the opposite hose? i understand people say it can have partial clogs....but even then you should have SOME heat....you can even feel the 2 pipes to see if they are hot to prove hot water is flowing through.

i think you have an airlock i suppose try putting it on a jack and bleeding it!

mine is possibly 1 of the fuses, sensors (the heater controls have a built in sensor) or possibly worst case scenario mixer flaps i reset cleared all the codes need to check again to see what it comes up with..

[khurmit]

Both pipes reach the same temp both hot. Did you have codes before? which ones? I've had none

[eg9_dc2]

i had a few codes for the ventilation flaps but the tests showed the worked fine they may have been old codes iv cleared everything but didnt get a chance to run again...thier was alot of heater related codes leading me to believe a blown fuse or something as everything cant just go faulty at once.....it also said something about an 'open circuit' im gonna check it tomorow

do you know how to use the full function of the dis?

you need to bleed your car on a tilt and take it from thier.....(with the heaters on hot of course etc).....

[doughboy]

Interesting thread.....

Logically, the heater rad pipes are top and bottom mounted (not bottom/bottom like a domestic water radiator) so any air will expel through the top hose.

If both hoses are hot then they are both full of water, and circulating OK.

For filling the system, no need to have heaters on hot and as that is only flap control, the water circuit is open continuously.

In theory there's no need for a water valve, it's just an uneccessary cost/failure point on the car.

[eg9_dc2]

i have had my car on a dis and i have no fault codes.ive had the coolant flushed out, changed, had the pipes from the core checked they are hot,had it bleeded with those vacuum tool things

i changed the thermostat even though it wasnt faulty and had no codes for it.

i read most of the temp sensors through the dis computer and they showed no faults and even moved up and down temps accordingly when i was adjusting the variables

my car was fine prior to running low with water from a small leak when the heaters went cold which is leading to believe it cant possibly be anything electrical?

my heaters have gone from blowing no hot air to blowing hot air for 25 seconds if i leave em off for about 20mins at a time with the car running upto temp

ive been advised to:

-change blower/resistor pack as it regulates temperature? i thought it only controls the fan speed?
-change the controls on the dash? i KNOW they have an internal temp sensor.
-possible fins on the water pump are broken? (not pushing the water around? theory doesnt make sense to me)
-partially blocked core? ...why would it let heat out for 25-30secs? and why would the pipes on the core be pretty hot..both of them (minus heat soak you can pretty much feel the hot water inside the pipes)
-bleed the car with the front end raised?

any advice please?

(OP sorry for the thread hijack i just thought my problems/info might be relevant to you to.il start my own post if you think its suitable.)

[khurmit]

No worries I can see you started your own thread. We can both hijack each others as it seems we have the same prob.

[khurmit]

UPDATE - BMW Master Technician has confirmed that there is no control valve on E9Xs with Automatic Dual Climate Control - temperature is controlled by flaps which pass the air over the Heat Exchanger (i.e. matrix) or AC Evaporator - basically a hot radiator and a cold radiator.

[eg9_dc2]

he is correct as i learnt from the links i posted they explain how you ihka climate control works in detail.
heater control is like a live valve at your control.