Ok, so I have a Model S 75D manufactured in 11/16 that I bought in 4/17. It was a demo unit with about 1,100 miles when I bought it. It now has 5,490 miles and I haven't had any problems until now. Two days ago I received a message on the IC that said "Car Needs Service - Power Reduced" with a yellow triangle after entering the car and stepping on the brake after the car sat in my garage overnight. There were also two yellow triangles on the energy meter and a dotted line indicating power was limited to 100kW. When I shifted into F or R, the entire P N R D display turned red. I drove the car a few feet and definitely felt the reduced power. I went to the E-Brake and Power screen and selected the Power Off option. I let the car sit a few minutes and turned it back on. No error was displayed. I called my local SC to see what they had to say. They asked for a description of the error and the time and said they would pull the logs and get back to me. They called an hour or so later and said I should bring it in to have some cables checked for possible water intrusion. I dropped the car off and they had it the remainder of that day, plus the entire next day. They updated the software from 17.28.c528869 to 17.28.4cf44833 first thing. They told me they checked all the appropriate wiring in accordance with California engineers and found no problems. Of course, the first evening, the new 17.32.9ea02cb software was released, so I asked them to install that before giving the car back. So today, I get the car back and drive it around for a while without issue and park it back in my garage. Five hours later, I get back in to go out and the SAME ERROR shows up again. Now I'm obviously upset and the SC is now closed for the week. I called what I believe is the California number and they say they can't pull the logs and can't do anything short of calling for a tow or I can contact my SC on Monday. I decline the tow and decide to wait until Monday. I leave for my errands in the old ICE and come back an hour later. When I get home I check the Tesla and the error is gone again! Has anybody else seen or heard of this intermittent "Car Needs Service - Power Reduced" error? I'm getting a feeling this is going to be a real back and fourth with my SC and they never seem to have any loaner cars available either.