HVAC blower intermittently does not work. Solution: wiring is faulty

[M.Hagen]

Originally Posted by jdamore

Thats a good thought.. I know exactly what you are talking about but it is not true for me for two reasons: 1.In my case, the stain was large (3.5in diameter?) and there was another circle stain next to it (not under the wire) that was about the same size. 2. I have heard of the bower stop working because water gets by the seal at the bottom of the windshield. It gets into the blower and seizes it.. in some cases can temporarily be fixed by spinning the blower with a stick through the plenum above.

Did you get your plug fixed?

That makes sense... I didn't know there was a known leak path from the windshield.

I got my blower motor to work by just replacing the regulator and re-wiring the connection. Depinning the connector to salvage the smaller pin was a success, that required two sets of small flatheads (jewelers size) and some finesse. The two larger pins were a loss since the plastic around them had melted, so I trimmed back about 6" on both the larger gauge wires and soldered in new extensions and new pins. I also used some 1/4" braided sleeving leftover from another project to help keep the wires insulated.

The connector and pin set from Pelican Parts was a direct fit. Part numbers were from Bond_007's post.

[doogee]

This issue has just been recalled. Hopefully it's an actual solution. I've replaced my wiring twice now.

https://www.usatoday.com/story/money...res/828690001/

The recall covers nearly 673,000 cars including the 323i, 325i, 325xi, 328i, 328xi, 330i, 330xi, 335i, 335xi and M3 from the 2006-2011 model years. Also covered are the 2007-2011 328i xDrive, 335i xDrive and 335is, and the 2009-2011 335d.

Wiring for the heating and air conditioning system can overheat and cause connectors to melt, also increasing the fire risk, even when vehicles are unattended. Four drivers reported injuries. BMW says a wiring connection can corrode and in rare cases cause fires.

Dealers will replace the wiring and connectors.

[M.Hagen]

Originally Posted by doogee

This issue has just been recalled. Hopefully it's an actual solution. I've replaced my wiring twice now.

https://www.usatoday.com/story/money...res/828690001/

That is good to hear. Based on the common failure, it was surprising that BMW did not take action earlier.

If anyone has access to "the system" to show the TSB or technical details. I'm curious what the remedy is other than replacing components. You would think that there is change to the system (new regulator type, thicker wire loom, etc).

[scope951]

So it sounds like symptoms of the blower motor cutting out or not working would indicate a more urgent need for inspection and repair? If my blower motor has been working normally probably okay right?

Would it be safe to battery tend the car in the winter still? Even though the car and blower motor are off, tending the battery would energize the system, so theoretically there's still a chance of this happening right?

[rks68rt]

My blower fan was exhibiting the same intermittent behavior recently even though it's a 2013.
Took a look underneath and noticed the wiring, connectors and fan are all different than the recently recalled year's(2008-2011) pics on this thread. No burned out wires or connectors.....
(BMW must of known something was up in 2012 MY to warrant this change.....)
Took her into the dealer and found fan blower was bad and hard to turn(bearings), as indicated by the tech.
Replaced the motor and regulator at same time for sanity sake.
All is well again....

[decimation1]

Originally Posted by Shaun135i

This really should have been a BMW recall not something we have to hunt for before our cars catch fire!

Isn't this what the new recall is about?

[jdamore]

Originally Posted by decimation1

Isn't this what the new recall is about?

Yup! Shaun nailed it.

[Route 16]

Would unplugging the hvac harness do anything bad to the car? I just checked the wires and electric board, no burnt material, everything looks brand new. Despite that, I still have this code 279f "box blower actuation electric diagnostic"
I saw a old moisture mark, probably 3-4 inch diameter but looked around the surrounding areas, no moisture noted.

[MPower7]

Can someone point me in the right direction to take a look at this?

Thanks,

[Route 16]

Originally Posted by MPower7

Can someone point me in the right direction to take a look at this?

Thanks,

under your glove box, i think there are 3 torx screws, remove those, should be able to pull off that lower panel, look directly underneath the area, you'll immediately see 2 wire harnesses, pull that off look at the terminals, the part you just removed it from is being held by the same size torx screws (2 of them) remove that, pull off the 5 tabs on that piece and you'll look at the electric board. if everything looks good, just reverse the steps

[widebodym3]

Route 16 - just to let u know that this issue is now a recall check with your local bmw dealership for details. Thanks

[CoopDAWg]

Originally Posted by Speed-D

My 335d was having the same issue with the fan just deciding to stop working so I ordered a new fan speed regulator. Then I started having my ecu reset randomly while my car was parked. Then one unfortunate lunch break all power to my car was lost when I was at the Chinese restaurant parking lot until it randomly decided to spring back to life. After digging some I realized this was a symptom of the b+ cable connection at the back of the fuse box, but I called BMWNA and confirmed that there were no open recalls on my car suggesting the cable fix had already been done to my car.

Today while I was working on getting to the back of the fuse box to double check the b+ cable I found this same burnt and frayed connection at my regulator. Mine was so bad it actually fused the connector to the regulator so I had to cut the wires and order a new connector along with the pins for the connector and I'll have to get some wire to extend the harness back to the original length. I didn't check the b+ cable at this point because I ran out of daylight, so I'll get to that tomorrow.

What I wanted to ask us this; has anyone else lost power to the entire car/ecu when this short happened, or did I just randomly have two seperate issues occur at the same time?

Where did you order the new connector & pins?

[nekbreaker]

bmw issued I recall on the wire harness a/c motor blower for that issue I got mine done excuse me if this is not related