2000 323i heater goes higher without touching the controls?

Question

when i put on the heat for some reason the fan starts getting higher without me touching anything can anyone help with this , thanks

Answer 1

Yeah, seems like the car is having a mind of its own doesn't it? Well, I hope you haven't tried talking to it... anyway...

What you need is called a "final stage resistor".
You can buy this part from bavauto.com for $70. The dealer might charge a little more.

Part # : 64 11 6 923 204

This power resistor is infamous for failing in earlier BMWs and was redesigned after the production of our cars. The new one has a more efficient heat sink, with more thinner "fingers". See photo: http://forum.e46fanatics.com/attachment.php?attachmentid=126347&d=1116098549

You'll need to remove your glovebox to get access to the tight space in the passenger footwell. It took me a good 2+ hours to complete the job on my exact same BMW. Save a couple hundred bucks. You'll need a regular screwdriver, a torx driver, a good flashlight (I used an LED head lamp), a magnetic pickup tool.

Here're the instructions.
http://forum.e46fanatics.com/showthread.php?t=256286&highlight=final+stage+resistor

Be extra careful with the torx screws when you are removing and installing the resistor, if you drop the screw, it would be impossible to retrieve it. So have the magnetic pickup tool attached to the screw before fully unscrewing them out.

This is unfortunately one of the common failing items on the car. If you have an automatic transmission, make sure to change the transmission fluid out even if the dealer says it's a "lifetime fluid"... that's another item that could fail. If you have any other questions, join an online forum www.roadfly.org or talk to the friendly reps at bavauto.com.

Good luck.

Answer 2

that happened to me too; on my 99 323i. It also happened on my next car, a 2002 Audi A6. I thought it was just something they did automatically. It was a real pain; in fact it was my only complaint about either car. I wasn't aware that something was wrong with it, just thought it was the way the Germans built em.

Answer 3

i own a repair shop,and its the inside control unit that's going bad on it,that's whats causing this the thermostat control unit is built in to this one and it goes bad causing this to happen,you can get a new one or a used one from a wrecked car ,that would probably last as long,because a new one is very expensive for these cars,but that's whats wrong with it,i have replaced a few of those,but they don't give a lot of problems ,just occasionally one goes out,but its no big job to replace it,good luck hope this helps.