Diagnosing blower motor in 2003 X5 3.0

[Corellian Corvette]

Today I purchased probably the nicest condition E53 I have ever seen, from lady who was meticulous about it. The car drives (and smells showroom fresh). I paid peanuts for the car due to one potential risk - the blower motor doesn't work.

The story I heard was that it was working fine, it hadn't been driven for a while, she went out to start it on a very cold day and broke the door handle, then while warming up the car the blower "just stopped"

Now I have X5's that are way more beat up, way more abused with way more miles and the blower motor works fine, so the bet I took is that the problem is actually the resistor (or something else) vs. the blower itself.

Question is if there are good suggestions on how to test this. I have used the scan tool to run the blower motor - nothing happens. I have checked the big 50amp fuses in the glove compartment and they were all fine.

When I test the buttons on the heater panel I *can* hear the actuators move. Although I am aware the problem can be with the heater panel as well.

Any other tips on checking the motor itself? I'm planning to buy the resistor for it but wanted to see if there was any other diagnosis in the meantime.

Thanks!

[andrewwynn]

The blower is controlled by the FSU (final stage unit) aka FSR final stage resistor. (not remotely similar to a resistor that should not be used). It's aptly nicknamed the hedgehog which you'll immediately understand why when you see it.

It's a very common fault on every BMW since at least late 90s.

[Corellian Corvette]

Yup super familiar with the FSR. I guess the question I'm asking is while I'm waiting for one to arrive, is there a test I can do in the meantime just to confirm?

[andrewwynn]

I think I read that you can jumper out the right pins on the FSU connector. That said also I've taken out FSU and plugged back in to get it working again for a while


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[Corellian Corvette]

Ah got it. If I'm gonna go that far, might as well just replace. Thanks!!

EDIT - I'm posting a question in another thread you might be able to help with!!

[Clavurion]

Blower motor is easy to test from the connector on final stage. First measure supply voltage between pins 2 and 4. Then with two jump wires connect the voltage and ground directly to motor, pin 2 -> pin 5 and pin 4 -> pin 1.

The female pins on that connector can loose tension and connection over time. So when the connector is out clean the pins and use some contact paste. On my own X5 the problem was poor contact on that activation line from IHKA to final stage. As this is only low amp signal line there were no signs of over heating despite the poor contact stopping the motor.

https://bmwteka.com/wds/en/e53/e64507f5

[Overboost]

Originally Posted by Clavurion

Blower motor is easy to test from the connector on final stage. First measure supply voltage between pins 2 and 4. Then with two jump wires connect the voltage and ground directly to motor, pin 2 -> pin 5 and pin 4 -> pin 1.

The female pins on that connector can loose tension and connection over time. So when the connector is out clean the pins and use some contact paste. On my own X5 the problem was poor contact on that activation line from IHKA to final stage. As this is only low amp signal line there were no signs of over heating despite the poor contact stopping the motor.

https://bmwteka.com/wds/en/e53/e64507f5

Thank you so much Clavurion! I thought I had a blower motor failure and I am no longer able to do things for my X5 like pulling the entire dash to replace that blower motor. I was a week away from trading my 20 year old X5 in with 221,000 miles. You saved me a lot of money and stress with this simple test at the FSR. I don't know if you're still active on here but thank you so much for your knowledge.

[Happy]

Originally Posted by Overboost

I was a week away from trading my 20 year old X5 in with 221,000 miles. You saved me a lot of money and stress with this simple test at the FSR. I don't know if you're still active on here but thank you so much for your knowledge.

Ohh..Beee…

Noooo… No we can’t lose you brotha!

Mine has eaten up 3 already.


E53 RiPPeR
XOuTPoST jUNkiE
ReVELaTiON 22:21

[Overboost]

Originally Posted by Happy

Ohh..Beee…

Noooo… No we can’t lose you brotha!

Mine has eaten up 3 already.


E53 RiPPeR
XOuTPoST jUNkiE
ReVELaTiON 22:21

Still here Happy! Trying to get to 300,000 miles. Great to hear from you!

[andrewwynn]

Deer took out my e53 at 205.

Different deer tried to take out my e70 at 176. Car won that battle.

Good to see ya ob. Did you get blower running with a new FSR?

Deoxit Gold for the win