[crehop]

Prob going to sound like a noob but i searched a lot.. here's the issue

No ac or heat no air circulation at all.

What's been done

1. Replaced blower motor
2. Replaced blower motor resistor
3. Checked all fuses
4. Scoured the internet...
5. Went crazy
6 Posted this post.

E90 coupe, 2008

Any Ideas?

[Tambohamilton]

Get a decent cable, get INPA/ISTA/etc, check for codes. It'll save you time and money in the long run.

[marvinstockman]

Get a voltmeter and make sure you have 12 volts to the fan, and also make sure it has a ground.

[crehop]

I checked for codes nothing, but im using a bluedriver , good but not bmw specific. Ill look into that. The fan just randomly stopped working 1 time i turned on the car, so i dont see how it could be ground, but ill check that also.

[crehop]

No codes, weird noise from center of dash when you turn on the fan but no actual fan... really have no idea since i already replaced the blower and resistor...

[crehop]

Originally Posted by marvinstockman

Get a voltmeter and make sure you have 12 volts to the fan, and also make sure it has a ground.

This ended up being it, Wire was intermittent tho so whenever i pulled it down to check it worked, second time i checked, it was out. Recommendation to anyone hunting this down later. It actually eneded up being the 12v that failed.

1. Place Red lin in second from end pin and place black in end pin
2. wiggle wires while reading voltmeter see if it changes (mine was going from 0-12 )

It seems these were already replaced at some point probably due to the recall and they just tied up the wires with tape, well the solder must have cracked or something over time, anyways this is the issue confirmed by holding wire and trying ac (it worked) let go it turns off.. anyways was driving me crazy, thanks MARVIN!

[bmwbob89]

This is why a voltmeter can lead in the wrong direction. You need a test light as old school as that sounds. The bulb puts a load on the circuit the volt meter does not.
Make sure your test light used an incandescing bulb not an LED or it won't help you.

[CA6VTEC]

Originally Posted by crehop

Prob going to sound like a noob but i searched a lot.. here's the issue

No ac or heat no air circulation at all.

What's been done

1. Replaced blower motor
2. Replaced blower motor resistor
3. Checked all fuses
4. Scoured the internet...
5. Went crazy
6 Posted this post.

E90 coupe, 2008

Any Ideas?

Hello,

I had the same problem. I would turn on the AC/Heat and no air would blow out. Turned out my wiring was fried. I searched the BMW website for recall and I had one for the blower motor. They replaced by wiring, all good now.

https://my.bmwusa.com/safety-and-emission-recalls

[crehop]

Originally Posted by CA6VTEC

Hello,

I had the same problem. I would turn on the AC/Heat and no air would blow out. Turned out my wiring was fried. I searched the BMW website for recall and I had one for the blower motor. They replaced by wiring, all good now.

https://my.bmwusa.com/safety-and-emission-recalls

In my case they ALREADY replaced the wiring at the dealer, but the solder on the fix broke it looks like. So even if your wiring is already replaced, it could still be the issue.