2003 E46 FSR Getting too hot and failing?

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ibbo1966
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Car model: 2003 E46 325ti
Location: Rugby

2003 E46 FSR Getting too hot and failing?

Post by ibbo1966 » 02 Dec 2017, 18:03

I have 2003 E46 325ti which I have replaced the FSR (Final Stage Resistor) in twice in the last month. The first replacement FSR lasted lasted 1 week and the second lasted 2 weeks. Neither of the replacement FSR's were BMW original. The firsts was a Madlifr Garage brand purchased from Amazon, and the second was a Smartsense purchased from ebay.

The original reason for replacing the FSR was because the blower fan was not working, which was the same fault when the first replacement failed. The second FSR has failed with the blower fan on full speed all the time, even when the ignition is off and key removed.

When fitting the new FSR's the heater fan worked fine and the fan speed regulated as I adjusted the temperature on the digital climate control panel, but now that the second FSR has failed I wondering is something else is the root cause of the FSR failures. I believe the possible causes are as listed below:

1. Faulty FSR's? (I have read a few posts about the quality and reliability of after market FSR's)
2. I noticed that when I replaced the FSR's and the fan was working that although the fan speed changed automatically when I changed the temperature, the temperature of the air coming out of the vents was always the same i.e. always hot, just coming out faster or slower depending on the speed of the fan. I was expecting the temperature of the air coming out to change and am wondering if the constant hot air is cooking the FSR causing it to fail? - And ideas?
3. Any other ideas as to what could be causing the FSR to repeatedly fail?

Any help and ideas appreciated.

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M60NJP
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Re: 2003 E46 FSR Getting too hot and failing?

Post by M60NJP » 02 Dec 2017, 18:07

From what I've read, your point 1. is most likely!!

BMW part isn't silly money - ask Barons on here for a member price?

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