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Been having problems with my heater ever since fitting facelift heater controls to my pre-facelift Z4.

Basically, when i originally fitted the facelift controls, nothing worked, so i fitted the facelift controls with the pre-facelift circuit board (innards).

After that, all the buttons and dials light up, but it just blows cold air out the vents. The only way i can get heat is by using the 'hurricane' button in the middle of the airflow direction dial. This sends a huge mass of air towards the windscreen, but at least it's hot!

Tonight, i decided to remove it all again and have a look what the problem is. No matter what i do, i can't seem to get the airflow direction dial to physically change the airflow, even though the dial turns perfectly fine.

I plugged in the laptop and had a look at any errors stored and found this one in INPA. As soon as i clear the error, it comes straight back, so theres obviously a problem somewhere. A rough translation gives me something along the lines of potentiometer short circuit.
Any ideas? I tried to find out whether it was in transport mode, but i don't think you can on INPA. I tried using DIS but couldn't seem to get it working for some reason.

Next step is to buy another pre-facelift heater control unit and see what happens.

Not sure if this is of any help to you Ben?
http://www.pelicanparts.com/techarticle ... cement.htm

sound like transport mode to me.

Potentiometer just fancy word for heat control knob. So sounds like a dodgy connection to the circuit in the heater control unit.

did you disconnect battery and leave it for over 20 mins before unplugging control. When i switched mine over it put can into transport mode.

mac27040 wrote: ↑Wed Dec 13, 2017 12:18 pm did you disconnect battery and leave it for over 20 mins before unplugging control. When i switched mine over it put can into transport mode.

Unfortunately not. I thought it might have been transport mode, but everything else works perfectly fine. It's just the air flow direction knob and heat control knobs that work, but don't actually change anything when turned.

when you opened up the heater control to swap circuit boards you did line up the knobs so the lock in to turn the dial on the circuit board?

mac27040 wrote: ↑Wed Dec 13, 2017 4:42 pm when you opened up the heater control to swap circuit boards you did line up the knobs so the lock in to turn the dial on the circuit board?

Yeah, i thought i hadn't done that, so opened it back up at the weekend and made sure the protruding parts were sitting correctly.

I'm sure a small part of the circuit board came loose, but all looks ok.

Hoping that a new set of heater controls sorts ot out. Will just have to go back to pre-facelift ones.

what Version circuit board is in it? Facelift or pre-facelift? I couldn’t get the facelift to work so had to swap the boards over and use facelift casing with pre-facelift circuit board. All works correctly.

mac27040 wrote: ↑Wed Dec 13, 2017 7:26 pm what Version circuit board is in it? Facelift or pre-facelift? I couldn’t get the facelift to work so had to swap the boards over and use facelift casing with pre-facelift circuit board. All works correctly.

I think it's the pre-facelift one. I tried the other one i had and it didn't work at all, so i assume that's the facelift board.

Noticed today the air direction dial isn't lighting up (no green light on the dial), so it's definitely a faulty circuit board.

Probably best to buy another pre-facelift one and split it again.

Have you checked it’s not in transport mode?

mac27040 wrote: ↑Fri Dec 15, 2017 8:42 pm Have you checked it’s not in transport mode?

I wasn't able to find anything about transport mode in INPA and unfortunately i couldn't get DIS to load correctly, which apparently is the program to use to reset transport mode. Just my luck

Also think SSS v32 will clear it

Where abouts are you?

mac27040 wrote: ↑Fri Dec 15, 2017 11:40 pm Where abouts are you?

Essex, near the QE2 Bridge. I will give the SSS software a try and report back