Last December(6 months ago) I replaced the blower motor regulator on my 1989 300E. 2 weeks ago the fan suddenly quit. Fuse was fine I visually checked it and also with a volt meter for continuity. Plus I put a new one in anyway just to make sure. I tear it down, disconnect the regulator to it and apply 12 volts to the fan. Worked fine. I pull out the regulator take it off the heat sink and put it back on. Hook it back up to the fan turn the ignition on, fan starts up. Put it all back together and for 2 weeks it works fine then just quits. All three speeds- no fan. I go through the same process as I did 2 weeks before but this time fan does not work. I checked the regulator with a volt meter. red wire has 12v+ with ignition on. with engine running yellow wire has about 6 - 7v. voltage across red and blue was anywhere from 3 to about 4.8v. Any ideas?

 

The regulator is toast.
Replace it and you should have no further issues.


roy@pelicanparts.com



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Your right It was fried. I replaced it and works fine. I put that regulator in Last Dec. What do you think made it go so quick?

 

IMO:
* A minimal quality design.
* Poor quality control.
* Storage environment degradation.
* Shipping - handling damage/degradation.


roy@pelicanparts.com


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