Another "heat" issue...

[TC535i]

Here's my symptoms.

"cold" setting provides warm air... hot setting gets hotter as expected. Dial on dash vent works as well... but will never get truly "cold" fresh air.

When the aux heater is plugged in, it clicks continuously, every few seconds. When I got the car from the prev owner, the 3-prong plug was unplugged. When I plugged it in, the ticking started... but still no fresh air, just mixed (semi-warm, even if it's cold outside).

The "temp" dials on the climate control seem very "loose", easy to spin, little to no resistance. Is this right? They do get warmer when I turn them warmer, so maybe it's ok... are they "levers", or do they turn and change resistance instead of physically activating anything?





Any ideas where to start? If it's clicking, does that mean the valves are ok, or not necessarily? Hit it a couple times to check? How hard are we talking about hitting them here??

[acidfire52]

Pretty sure the dials just change resistance, as mine turn pretty easy too.

[Fetch]

Dials just change resistance.

Man, these things...
I have similar symptoms to you.

How does your a/c work?
Mine works very well, so long as the only vents I have it come out of are the driver & passenger door vent, & the big rectangle vent in between the defroster & the vents above the radio. (Actually it's pretty cold coming out of the passenger dial vent above the radio)

My system has something goofy going on with it, I'm just glad I can get it very cold or VERY hot in the car if necessary (wow the heating is ridiculous!).

I think the dial vents above the radio are fresh air vents/always mixed with some heat?

I was going to make this post more detailed but it's so hard to reference the different vents & levers for me, because I don't want to call them by the wrong name and confuse myself & others more.

Sorry, this doesn't really help the thread, just kinda 'venting' about how complex the hvac system is....

[TC535i]

I don't know about the A/C, I think it may be cooling, but mixed with hot air keeps it from coming out cold? I just got this car a week ago, so I'm still trying to figure certain things out, I don't have much of a frame of reference. :(

[acidfire52]

As my car came without a manual.. can anyone share exactly what the red to blue dial between the dash vents does?

Sorry to thread jack, kind of related.. :p

[brick8]

red to blue mixes outside air with heated/cooled air running through center vent in dash (common feature on many European cars).

[acidfire52]

Cool. Simple enough :D

[shogun]

You can download the owners manual from this board, use the search for 'owners manual online'.
And the system works like this
http://bmwe32.masscom.net/johan/center_vents/air_distribution.jpg
http://bmwe32.masscom.net/johan/center_vents/center_vents_v1.1-1.html

http://bmwe32.masscom.net/johan/ihka/ihka.html

http://www.bimmerboard.com/forums/posts/283291

[TC535i]

I don't know about the A/C, I think it may be cooling, but mixed with hot air keeps it from coming out cold? I just got this car a week ago, so I'm still trying to figure certain things out, I don't have much of a frame of reference. :(

To clarify... the A/C light comes on, and the motor stumbles, I can tell the compressor's firing up... so I think it's working. It's just mixing.




Here's my #1 question... If the heater is "clicking" constantly every few seconds, is it still possible that the valves are stuck open? Or is the "sticking valve" syndrome usually sticking CLOSED, and the fact that mine's open indicate that something in the electical system isn't working?

[Paul in NZ]

i think the clicking you can hear is caused by the fac that one of your heater vaves is ion the verge of sticking open,and you have enough build up of crud on the valves that the vales cant close completely and always let warm water through to the heater core......you talk about the aux pump causing the clicking.....next time your take the car out,when you come home make sure it is clicking then unplug the aux pump...does it stop?My clicking stops if i turn the heater down.....ie to cold

[shogun]

The aux pump does not click, the heater valves click and if they do not click they are bust.
If the aux pump clicks there is something wrong. It switches on at a certain temp in the cooling system and does not switch off.
Check the potentiometers on the dials
check the heater valves

and report back in detail with test result.

Have you ever checked the temp sensor behind the climate control panel?
Might be completely dirty and giving wrong signals.
http://web.archive.org/web/20020813003134/maxf.freeyellow.com/ac_cont/acc_drt1.jpg
Some in Germany even resoldered the IHKA control module, the control panel and still they had probs with temperature adjustment.
Then they bought a new sensor and soldered it in and prob was solved.
It is said to be a TNC-resistor with an R25 of 10k Ohm.

[TC535i]

i think the clicking you can hear is caused by the fac that one of your heater vaves is ion the verge of sticking open,and you have enough build up of crud on the valves that the vales cant close completely and always let warm water through to the heater core......you talk about the aux pump causing the clicking.....next time your take the car out,when you come home make sure it is clicking then unplug the aux pump...does it stop?My clicking stops if i turn the heater down.....ie to cold


If the 3-pin circular connector is removed... it stops clicking. If it's plugged in, it clicks every few seconds.