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DMC Fan Motor Fault

While out for a nightly spin I got a flash on the VDS that seemed to say " DMC Fan Motor Failure .... or Fault" but it flashed on the screen, beeped and went away so fast I didn't really see it. I thought of the PEM cooling fans but while driving I kept checking the temps and nothing was abnormal. When I got home I plugged 992 in and issued a "cooldowm" command on the OVMS and cooling started normally BUT after two minutes I got this: "DMC FW: HCS Faulted Warning"! Cooldown paused.........

Anybody seen this??? :crying:

Issued a second cooldowm request and nothing happened....... No charging at all.

Started a standard charge by pushing "charge now" on VDS one charging started and seems to be running in "Range Charge"! The front AC fans engaged for awhile but stopped after a few minutes.
Battery at 82f, motor at 109f; PEM at 104 F charging continues.
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Well ..... Charged normally in Standard Mode" over night to 172 miles. That's normal for my battery. Temps: 78F for battery; 89F for motor; 91 for PEM........ Little hot for motor and PEM but not too abnormal. garage usually stays below 80 F at night so motor above ambient after 12 hours. PEM hot because early morning charge heats it up. Battery stayed cool so I know AC fans in front operating normally. Worried about PEM fans in back.

After reading another thread on the forum the original flash message was probably "DCM Motor Fan Problem" and showed up because VDS was left in debug mode after last service. I like the temp readings on the display screen while in debug mode so I didn't have it changed. The second warning was as stated.

Just viewed a PEM cleaning video from mgemmell and was very impressed with the problems cleaning the PEM and potential for fan motors to inadequately cool in the face of "gunk" in the ducts. My warning may be related to "low fan revolution" or blockage in ducts. Had my service in June so not sure what is cause.
Called Service Rockville and was told that they would call me back........ So I wait.
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Model 3 Performance
Aug 28, 2011
Toronto, Canada
I had a similar message pop up today "DMC PEM Fan Problem". It's a debug message, not a critical alert, so I'm not overly concerned but will check with service. The fan seems to be operating normally by ear and the PEM temperature is fine even during spirited driving in Performance Mode.


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