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My 2021 is having electrical problems

9620 Views 13 Replies 8 Participants Last post by  dario.atallah
Hi. Has anyone had any electrical problems?? My 3 week old is at the dealer and they haven’t been able to locate the problem yet. Wouldn’t start today, had to jump it. The alarm went off in the middle of the night, I turned it off and secured it. Then wouldn’t start when I woke up a few hours later. Battery tested and no problems.. has anyone any ideas what it could be?
Thanks!
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@Lancer3, can you try these steps to reset the battery management system?
  1. Get in vehicle, close doors
  2. Turn on ignition (but don't start)
  3. Wait for battery light to come up
  4. Flash brights 5 times
  5. Press and release brake 3 times
  6. Battery symbol on dashboard should flash after 5-10 seconds
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@Lancer3, can you try these steps to reset the battery management system?
  1. Get in vehicle, close doors
  2. Turn on ignition (but don't start)
  3. Wait for battery light to come up
  4. Flash brights 5 times
  5. Press and release brake 3 times
  6. Battery symbol on dashboard should flash after 5-10 seconds
I took to the dealer and they reset the BMS. Seems to be doing ok now. Hopefully it doesn’t drain again! Thanks for sending the sequence over. I’ll try that myself if it happens again.
Hi. Has anyone had any electrical problems?? My 3 week old is at the dealer and they haven’t been able to locate the problem yet. Wouldn’t start today, had to jump it. The alarm went off in the middle of the night, I turned it off and secured it. Then wouldn’t start when I woke up a few hours later. Battery tested and no problems.. has anyone any ideas what it could be?
Thanks!
Is your alarm factory installed or dealer installed. I had the problem you have described on a 2011 F150. Turned out the dealer incorrectly installed the alarm system power connection. Once the dealer fixed I never had a problem.
@Lancer3, can you try these steps to reset the battery management system?
  1. Get in vehicle, close doors
  2. Turn on ignition (but don't start)
  3. Wait for battery light to come up
  4. Flash brights 5 times
  5. Press and release brake 3 times
  6. Battery symbol on dashboard should flash after 5-10 seconds
Thank you so much!! I have a new 2021 F150 for 3 wks, 2245miles on it. Just drove from Wyoming to LA for a funeral. No problems during trips. This morning came out - vehicle totally dead. Wouldn't respond to key fob had to enter with the mechanical key in the fob. Again totally dead, no response to anything. I put on a battery charger, showed battery 100% ok, slowly got some response on dash lights/screen but no response to starting. Called the emergency # for Ford, talked person who was to send tow truck, 4 hrs later nothing, attempted to call service dept at local Ford, voice mail and that too was filled - no body available apparently cause approaching labor day weekend. While waiting, came across your post and thought skeptically worth a try. Guess what it worked, everything ok except get a message to "turn off the ignition or start engine..". However ignition is off. So my dilemma is do I dare take into the traffic and drive back to Wyoming? Ford has had these problems but apparently won't tell us why. My local Wyoming Dealer service department that at least answered the phone - no idea and resarching problem. Again thank you.
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I just bought 2021 F150 Crew Cab XLT Sport 2 weeks ago, has 1026 miles on. I stopped to drop my son off, the auto stop shut the truck off, when I let off the break trucked wouldn't start. Put it back in park and tried for 20 min, using remote start, trying everything I could think of. Finally started and to it to dealer. They put computer on and had code for the starter, but it never dated when. I never received anything on ford pass app. Any ideas?
I just bought 2021 F150 Crew Cab XLT Sport 2 weeks ago, has 1026 miles on. I stopped to drop my son off, the auto stop shut the truck off, when I let off the break trucked wouldn't start. Put it back in park and tried for 20 min, using remote start, trying everything I could think of. Finally started and to it to dealer. They put computer on and had code for the starter, but it never dated when. I never received anything on ford pass app. Any ideas?
I checked original battery voltage every AM for a week while awaiting Ford appointment. Averaged about 11.2-11.5 v too low and Ford checked battery and replaced with new AGM. As noted on another thread, purchased Audew Battery booster for under the back seat since tailgate won't open when battery dead. I also purchased a none obtrusive battery monitor that plugs into cigarette lighter outlet so can monitor voltage. It also has two outlets, large and smaller where can plug in phone. Battery most mornings before starting about 12.5v. I would insist on Ford giving you a new battery and turn off the auto start button until they do.
We have a 2021 Ford F150 had it for a year now. This past winter all of a sudden dash lights flashing ,one code said service truck then in wouldn't start. The next day it started. Now 3 months later same lights flashing wouldn't start. Had it towed to our Ford dealer it's been there a week no diagnosis yet. Also anyone do you heard your truck qlinking all the time like its looking for the key? That's been happening since it was new. The service department told me it's nomal they all do it ,well this is the first F150 that we have had that dose this all the time and we owned Ford trucks forever. Just wondering if its linked to what's going on with our truck. I seems like electrical.
Hi. Has anyone had any electrical problems?? My 3 week old is at the dealer and they haven’t been able to locate the problem yet. Wouldn’t start today, had to jump it. The alarm went off in the middle of the night, I turned it off and secured it. Then wouldn’t start when I woke up a few hours later. Battery tested and no problems.. has anyone any ideas what it could be?
Thanks!
Had the exact problem with my 21 Lariat. Its the alternator. The alarm would go off during the night, I would get messages on the Ford pass app. Here is the issue, the trucks computer registers the amperage to a T. when it falls below its set amperage all the bells and whistles fail, but the battery shows that's its good. I took my truck to ford for weeks on end. I was sick of this crap! They finally plugged the truck into a laptop and monitored the trucks amperage. They thought the alternator was defective but couldn't prove it to get ford to replace it. Finally a tech decided enough is enough and replaced the alternator. Problem solved!! all the issues went away.

I'm on a new one now though with my right driving light! It keeps going off and on. Ford cant find the short and the error messages keep showing up on my dash!! OMG!!! its been at the dealer for two weeks trying to figure this one out! The Ford rep is scheduled to look at it next week.
We have a 2021 Ford F150 had it for a year now. This past winter all of a sudden dash lights flashing ,one code said service truck then in wouldn't start. The next day it started. Now 3 months later same lights flashing wouldn't start. Had it towed to our Ford dealer it's been there a week no diagnosis yet. Also anyone do you heard your truck qlinking all the time like its looking for the key? That's been happening since it was new. The service department told me it's nomal they all do it ,well this is the first F150 that we have had that dose this all the time and we owned Ford trucks forever. Just wondering if its linked to what's going on with our truck. I seems like electrical.
Had the exact problem with my 21 Lariat. Its the alternator. The alarm would go off during the night, I would get messages on the Ford pass app. Here is the issue, the trucks computer registers the amperage to a T. when it falls below its set amperage all the bells and whistles fail, but the battery shows that's its good. I took my truck to ford for weeks on end. I was sick of this crap! They finally plugged the truck into a laptop and monitored the trucks amperage. They thought the alternator was defective but couldn't prove it to get ford to replace it. Finally a tech decided enough is enough and replaced the alternator. Problem solved!! all the issues went away.
I have had the same problem since Feb 4. I took it to the dealer who had replaced a defective battery 2 weeks earlier. They ran tests and this time it showed a defective alternator/starter. I think this is the DC/DC Converter between the AGM battery and the hybrid battery. My part is supposed to come in on Mar 31, 2 months since I took the truck to the dealer. To their credit, they rented a nice RAM 1500 for me.

My F150’s battery dropped its voltage to 11.7V overnight. One morning is was 5.4V. I wish I had known about the trick to reset the BMS. I charged the battery slowly for 36 hours and I was off working again. But the battery kept discharging overnight.

The rental’s battery is always above 12.3V, even if I don’t drive it for more than 2 days.
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