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ComradeNick
08-20-2018, 01:21 PM
I disconnected the negative terminal on the car battery in order to work on Installing a new radio head unit just to be safe. Upon plugging everything in and reconnecting the battery everything works fine including the radio, expect the hvac module.

Whats interesting is the A/C is still blowing and when I turn on the headlights the buttons on it glow orange along with the rest of the car. In position 1 the buttons glow and air blows, but no control. In position 2 the lights turn off and no control. The buttons don't do anything and no numbers display on the screen.

No check engine lights, car starts fine. If anyone has an idea how to reset the unit or has run into the this let me know. Thanks.
Oli77
08-20-2018, 06:05 PM
Sorry, don't understand what position 1 and 2 refer too? Key position?

Maybe related to some wires that were pulled when you were working on the radio?
ComradeNick
08-20-2018, 08:59 PM
Sorry, don't understand what position 1 and 2 refer too? Key position?

Maybe related to some wires that were pulled when you were working on the radio?

Yes key position. In pos 1, orange night lights come on. Pos2 and when the car is on, the lights go out.

What i'm looking into is why the unit isn't turning on and controlling the A/C. Right now all it does is blow air, which has been warm so far. What I've looked into so far:

1. Checked fuses 28, 62, and 63; all fine. I removed and replaced all three, no change but removing 28 makes the fan blower stronger than when it is in.
2. Looking into if the car fell into "transport mode" this seems to be common especially in z4s when the battery is disconnected, but also in some e46s. I will have go to a mechanic to test this.
3. I nicked a wire when I was unplugging the unit, I checked the wires several times and doesn't seems to be the case.

I'll keep looking into it and will likely give my mechanic a call in the morning.
ComradeNick
08-21-2018, 03:21 PM
Alright looks like I fixed the issue.

One of the power cables going into the HVAC module was bent out on the plug, I was able to push it back in and secure it. This makes sense there was still some power going into it, just not the wire which controlled the module itself.
Oli77
08-21-2018, 05:11 PM
You are the master of your own destiny! Good job man! Fixed it!