High voltage? System shut down while driving

[FordTechOne]

All modules on the vehicle have a threshold at which they will shut down to protect themselves in the event of high system voltage. Since you were seeing up to 16V, that is most likely when various modules began to power down and reboot. Due to the module protection strategies, it is unlikely that anything was damaged by 16V. Once the cause of the issue is diagnosed, the tech can then do a battery test to verify that the battery wasn’t damaged.

 

[KingKoopa17]

Well, better safe than sorry, especially when you have options. Let us know what they find, maybe just a loose battery connection, lol. One could hope, anyway.

Weeeeell, wouldn't you know it... Checked the connections during my lunch and lo and behold: Wiggled the wire on the positive terminal and heard sparks. That nut was hardly on. Should've heeded the advice from your first post, lol.

All modules on the vehicle have a threshold at which they will shut down to protect themselves in the event of high system voltage. Since you were seeing up to 16V, that is most likely when various modules began to power down and reboot. Due to the module protection strategies, it is unlikely that anything was damaged by 16V. Once the cause of the issue is diagnosed, the tech can then do a battery test to verify that the battery wasn’t damaged.

Good to know! Didn't know any of that and certainly gives me some peace of mind. So there was the loose connection on the positive, am I out of the woods? Dare I take it back home? I checked the voltage afterwards and read 14.5v. Don't know if that's quite normal after start-up, so should I take it in for service to be on the safe side?

 

[smurfslayer]

Hot damn! That's crazy. Definitely considering myself lucky then! I'm hoping it's a quick fix as well, but now I'm beginning to wonder if it isn't related to the stock battery that randomly died on me back in March after four months of ownership...



One other question though, would it be safe enough to drive it onto a flat bed and at least have it towed home? I might be able to have my dad bring his Super Duty and his flat bed at the expense of a steak dinner and at least bring it home, then have it towed from home to the dealership tomorrow. Or, and I'm assuming this would be the better option, should I simply not touch it? I only ask since the dealership in which I bought it from and intend to take it to is even further away from where I work. Just looking to save myself a long trip, if I can.

A failed or failing regulator will cook a battery, I’ve had a mechanic warn me about that when I was.... 17 or 18. I didn’t have a lot of cash so I got the regulator repaired only. Not long after, I replaced the battery, it was dead one morning when I was heading to work. Several vehicles later, I had another v/r go, replaced regulator, but had a pretty new battery, so I chanced it and did not have any issues.

When the Duck regulator went, it cooked 2 batteries, my old one, which lived on a battery tender but was about 4 years old and my fancy new Shorai lithium iron. Once I knew the regulator was dying or dead for a fact I was nervous about being invisible (on the bike, lights are always on but when the regulator dies, the circuits go out, so no headlights, brake lights or signals).

@FordTechOne confirms the electronics will scram before permanent harm, but, I still maintain you don’t want them scramming while you’re driving, so I’d be ok driving it on to the flat bed but I wouldn’t take it further than around a city block.

 

[KingKoopa17]

A failed or failing regulator will cook a battery, I’ve had a mechanic warn me about that when I was.... 17 or 18. I didn’t have a lot of cash so I got the regulator repaired only. Not long after, I replaced the battery, it was dead one morning when I was heading to work. Several vehicles later, I had another v/r go, replaced regulator, but had a pretty new battery, so I chanced it and did not have any issues.

When the Duck regulator went, it cooked 2 batteries, my old one, which lived on a battery tender but was about 4 years old and my fancy new Shorai lithium iron. Once I knew the regulator was dying or dead for a fact I was nervous about being invisible (on the bike, lights are always on but when the regulator dies, the circuits go out, so no headlights, brake lights or signals).

@FordTechOne confirms the electronics will scram before permanent harm, but, I still maintain you don’t want them scramming while you’re driving, so I’d be ok driving it on to the flat bed but I wouldn’t take it further than around a city block.

Jeez. I'll definitely keep an eye on it in the future and will mention it to the tech when I see him. Like I said above, the nut was pretty loose on the positive terminal of the battery when I checked it, tightened it down, started the truck and checked the voltage, it's only reading at 14.5v. Now I'm wondering if the issue is resolved or should still play it safe and have it towed to a dealership? Flat bed might not be the case, so roadside it is, if that's the route I should take. Thanks to everyone for all the help and advice, by the way!

 

[Mike K]

I had something weird happen for the 3rd time yesterday. When I pulled out from my house, the touchscreen was frozen on Audio, but no music..it wouldn't react to touching the screen to try and change what it was stuck on. So no music...I did have my Iphone plugged in..I had to stop turn off the truck lock it and wait for the screen to go off..then I got back in and ouilla back to normal...

This has happened before, but the screen went black and was unresponsive, until I did the same thing to get it back to norm..

Any ideas?
Mine is a 2019, bought from dealer w 26K miles...so still under factory warranty.
Thanks.

 

[FordTechOne]

Good to know! Didn't know any of that and certainly gives me some peace of mind. So there was the loose connection on the positive, am I out of the woods? Dare I take it back home? I checked the voltage afterwards and read 14.5v. Don't know if that's quite normal after start-up, so should I take it in for service to be on the safe side?

14.5 is normal charging voltage; it will vary depending on electrical load and driving conditions. If everything is operating properly after tightening the battery terminal, you’re probably fine. Wouldn’t hurt to have the dealer test the battery just to verify it wasn’t damaged.

 

[FordTechOne]

I had something weird happen for the 3rd time yesterday. When I pulled out from my house, the touchscreen was frozen on Audio, but no music..it wouldn't react to touching the screen to try and change what it was stuck on. So no music...I did have my Iphone plugged in..I had to stop turn off the truck lock it and wait for the screen to go off..then I got back in and ouilla back to normal...

This has happened before, but the screen went black and was unresponsive, until I did the same thing to get it back to norm..

Any ideas?
Mine is a 2019, bought from dealer w 26K miles...so still under factory warranty.
Thanks.

Your phone may not be compatible with the system (depends on model) or you may have an app on your phone that is pulling the system down. If the issue only occurs with your phone paired or plugged in, that is your most likely cause.

 

[smurfslayer]

Jeez. I'll definitely keep an eye on it in the future and will mention it to the tech when I see him. Like I said above, the nut was pretty loose on the positive terminal of the battery when I checked it, tightened it down, started the truck and checked the voltage, it's only reading at 14.5v. Now I'm wondering if the issue is resolved or should still play it safe and have it towed to a dealership? Flat bed might not be the case, so roadside it is, if that's the route I should take. Thanks to everyone for all the help and advice, by the way!

Like FTO said, keep an eye on it after tightening the post, maybe you fixed it.

 

[KingKoopa17]

So, thought I'd give a little update: before I left work yesterday I grabbed my DMM for gits and shiggles to check the voltage while the engine was off and got 12.39v. Not sure if this qualifies as checking the battery life. Drove it home, kept a keen eye on the volts the entire way back and stayed at a constant 14.5v. Stopped by my dad's place since he has an OBD scanner and wanted to check for any possible faults and found none. Upon leaving the voltage dropped down to 13v while driving. Drove it today and it was reading only 12v, but it did fluctuate from 12.5v to 14.5v. It did still read 12.4v on my DMM while the engine was off, however. Called the dealership and let the tech know my situation, although he didn't seem too concerned about it. Just said to give them a call if I saw it drop below 12v or experience any other issue. If that's ever the case, I'll be sure to give an update.

 

[smurfslayer]

it sounds like you fixed it. I’ll happily defer to @FordTechOne on the specific ranges of voltage you want to see here but it does sound -generally- ok. Like he said earlier, charging will vary based on load so there’s a lot more involved on the modern truck.

I would not have guessed a loose batter connection with the super high voltage but ... live and learn.