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Sudden Inability to Charge Via Timer

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My electric provider (SCE) makes it quite advantageous to charge my MS60 between midnight and 6 a.m. I therefore had my electrician install a timer that turns on the power between these hours. My practice since I acquired the car in October has therefore been to connect the charger cable to the car's charge port when I come home in the evening but, of course, the actual charging only takes place when power becomes available at midnight. This seemed advantageous compared to "scheduled" charging via the dashboard app because I can control both starting and stopping time.

This system worked well until two nights ago. That night the car did not charge at all even though the timer was working perfectly, the charger cable was properly connected, etc. So last night I followed my usual practice in connecting the car for charging and woke up between midnight and 6 a.m. to see what was going on. Again the car was not charging. I attempted to use the app on my iPhone,, which showed the charging cable connected to the vehicle but, despite repeatedly pressing "start charge" it would not charge. So I went to the garage and again confirmed all was properly connected. The power indicator on the charging cable was lit green, showing power was available, but the port was red colored, not green. I removed the charging cable, reconnected it, and this time it worked properly.

The only thing I can think of is that perhaps the car no longer will charge if the charger is connected with the power is not yet activated. But that makes no sense to me as the car has scheduled charging, and this has worked fine up until now. And, of course, it did charge when I physically reconnected the charger.

I don't think it is relevant but I am using the new replacement adaptor.

Has anyone encountered this? Does anyone have a theory? I will see what happens tonight, of course.
 
A workaround to consider: Set your timer so power is on when you typically plug your MS in and off at 6 a.m.; set the MS scheduled charging to begin between midnight and 6 a.m.

Doing this always insures the car is being charged at the lowest rate. Also, using a little math, one can work out the charging amps needed within a time period to charge the car to the percent desired. I have done this on occasion to give me control over having a "full tank" just before leaving on a trip without the worry of having the battery charged to full longer than necessary.

The UMC has a reset button on it at the head unit; try pushing it to see if a reset of the UMC corrects the fault.
 
A workaround to consider: Set your timer so power is on when you typically plug your MS in and off at 6 a.m.; set the MS scheduled charging to begin between midnight and 6 a.m.

Doing this always insures the car is being charged at the lowest rate. Also, using a little math, one can work out the charging amps needed within a time period to charge the car to the percent desired. I have done this on occasion to give me control over having a "full tank" just before leaving on a trip without the worry of having the battery charged to full longer than necessary.

The UMC has a reset button on it at the head unit; try pushing it to see if a reset of the UMC corrects the fault.

Thank you, Tommy. I have done all of these things and look forward to seeing if they make a difference. However, now the Tesla app on my iPhone is not communicating with the car so I am bit concerned this may all be due to a larger issue.
 
Most timers are not able to handle the amperage that the Tesla draws. I suspect that you have burned a connection in the timer. Why are you not using the function provided by the car itself? I understand the start and stop times, but with a 60 your charge times should not exceed 6hours.
 
Why are you not using the function provided by the car itself? I understand the start and stop times, but with a 60 your charge times should not exceed 6hours.

Agree with this. And why the concern with the stop time when charging will automatically stop once the pre-set charging limit is reached? you may also be right that having the UMC connected without power (because the wall timer is off) may contribute to the problem.
 
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I wanted to control when charging stopped to ensure that it did not continue after 6 am when our rates dramatically increase. Six hours of charging (midnight to 6 am) may on occasion be insufficient, such as when battery power is low and I have the charging set for a full charge. That being said, this would occur only occasionally, so I am satisfied with the new setup, as suggested. Thanks to all for the input. This is a great community.