He's dead Jim! Whodunit? 12 V or HVBJB, place your bets!

[mwtechy]

Sounds very similar to the issue I had earlier this year. I was stuck on 1.7.1 for a long while. It got updated to 2.7.2 the week before my 12v died which the wiki currently claims had a BECM update. This was pre HVBJB recall update. Tow truck driver also had to get through around 4 different charge attempts to power things on just enough to get it into neutral both getting it on the flatbed and rolling it off at the dealer. They wound up replacing the 12v, the BECM, and cracking open the HVB just to test the cells as some weird charge got on some of them. Since then I haven't seen an issue and have received two powerups to 2.7.4 and the recall software but still missing bluecruise. I would assume something else is going on with the BECM or software on it causing a number of similar problems but to suggest it on this board is blasphemy. I don't think you can really trust any of the codes that come up when 12v fails, sure one or two of them are correct but the rest are nonsense as they were just freaking out due to the 12v failing from my understanding. The 12v in your mme is Def not a gaming pc backup power supply.

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[Mach-Lee]

The final of three jump starts was from a running 2003 Hyundai 4-banger. MME still wouldn't actually "start".

Also, interestingly, my ford pass won't start anymore. Just sits there at the Ford logo while "loading".

It seems very strange to draw a ton of power for the modules. I mean... I'm a software engineer and I build my own gaming PCs from parts. I have for long enough my first gaming PC (that I don't own anymore, but...) could legally drink. I have a UPS in my setup which isn't much more than a big old 12V lead-acid battery and an inverter. Sure if I'm gaming I'll have a 5-10 minute run time, but if it is just idle it'll be more like 30+ at a 200W draw. And that's a desktop PC with a power-hungry GPU, two displays, the router, dsl modem, desk lamp, ...

If it won't jump start from a running vehicle, then your 12V battery is probably toast. Maybe a shorted cell sucking up all the power. Last time I heard something similar happen, it was because a groundhog chewed wires in the car and drained the battery. Any rodents where the car was parked?

I think the idle draw of the Mach-E was like 250W last time I checked? The modules draw a lot more on startup just like your computer while booting. Since there are like 40+ modules the starting amps add up.

FordPass not starting is a known bug not related to the car, force quit, wait 10 sec, and retry.

 

[jbooth]

If it won't jump start from a running vehicle, then your 12V battery is probably toast. Maybe a shorted cell sucking up all the power. Last time I heard something similar happen, it was because a groundhog chewed wires in the car and drained the battery. Any rodents where the car was parked?

I think the idle draw of the Mach-E was like 250W last time I checked? The modules draw a lot more on startup just like your computer while booting. Since there are like 40+ modules the starting amps add up.

FordPass not starting is a known bug not related to the car, force quit, wait 10 sec, and retry.

Large rodents no. Small rodents (mice, voles) are possible, we back up on park land so yeah they're around. Never had any car trouble or heard of such from the neighbors. I'm not saying it isn't possible, since clearly it is, but no evidence of such at the moment.

250W idle draw is madness. What chips are they running, old pentium pros?

I was going to say the fordpass workaround didn't, but after a couple cycles of it, it finally did.

 

[HuntingPudel]

You might think it’s madness, but there are many separate computers inside of the MME. Their power draw is additive. Just in the process of reprograming some of the modules there is > 40A of current being drawn. When everything is computing together, it’s a serious poop show of power draw.

 

[jbooth]

You might think it’s madness, but there are many separate computers inside of the MME. Their power draw is additive. Just in the process of reprograming some of the modules there is > 40A of current being drawn. When everything is computing together, it’s a serious poop show of power draw.

I understand how distributed systems work, that's pretty much been my technical field my whole career. Not embedded, but server side, be that supercomputer or large (geographically) distributed data systems.

I'm not in embedded systems, and I understand there is a difference between aircraft/automotive and consumer/enterprise gear. And yet, 250 watts is still madness.

 

[Shayne]

Sounds very similar to the issue I had earlier this year. I was stuck on 1.7.1 for a long while. It got updated to 2.7.2 the week before my 12v died which the wiki currently claims had a BECM update. This was pre HVBJB recall update. Tow truck driver also had to get through around 4 different charge attempts to power things on just enough to get it into neutral both getting it on the flatbed and rolling it off at the dealer. They wound up replacing the 12v, the BECM, and cracking open the HVB just to test the cells as some weird charge got on some of them. Since then I haven't seen an issue and have received two powerups to 2.7.4 and the recall software but still missing bluecruise. I would assume something else is going on with the BECM or software on it causing a number of similar problems but to suggest it on this board is blasphemy. I don't think you can really trust any of the codes that come up when 12v fails, sure one or two of them are correct but the rest are nonsense as they were just freaking out due to the 12v failing from my understanding. The 12v in your mme is Def not a gaming pc backup power supply.

I agree from my experience when the 12V goes down it appears the brain has no power and just spits out a stream of stupid stuff with no one SVS or SSN. It does spit out SSN in the stream but it is parked and will not go in gear. Never got the rear end message.

The 12V is not the power supply it is more like the silver dollar cmos from what I understand. Believe the 12V is bypassed by the dc to dc to feed the car and it just places 15/13V on the 12V to charge it. Until the dc to dc (12V power supply) fires up it needs to boot off the CMOS (12V). Many uefi's now boot when the cmos battery dies but some not well or need to be in the default settings which sometimes will not let the OS boot unless you know how to config the bios. This car does not boot well at all when the 12V is dead (low) have no idea of the energy required to close the contacts and power the dc to dc.

The cmos on this car is a rechargeable battery and dying when it has 85% of a 100 KWh battery and is plugged into 240VAC leads you to believe the logic or the hardware just does not charge it. Not a lack of power. Guessing logic BECM or the HVJB but it could even be the dc/dc (big pack feeds it). That is baring a short or the cheap 12V fix which I was sent home with to try and the result was it is not that. Could be different things that kill the 12V and yours may be was bad BECM software logic/install? Your vehicle is in a deep dead sleep can not help. Can't be closing those contacts too many times.

 

[jbooth]

<barenaked ladies>It's been... one week since it stranded me</barenaked ladies>

And nothing useful yet. I have a case from FoMoCo and they're doing okay, even offered that they'd pay for the tow it to another dealer, but I can't get through on the phone to any other nearby service when I tried on Saturday so I'll likely just end up leaving it where it is. By the time I can get through and get an appointment, the local tech should hopefully be back?

Also spending 2-3 hours babysitting it to a different service location during the day isn't really in the cards anyway.

 

[jbooth]

Well someone did something with it this morning. That's the good news. The bad news is Fordpass just lit up with a bunch of faults. Pre-collision assist not available, four copies of hill start assist warning, and a high-voltage battery warning claiming "the powertrain control system has detected that the system power supply voltage is lower than desired."

Fordpass still seems to be reading 75% SoC on the main pack, but how much I should trust fordpass to be up to date with reality, or the reliability of that reading is a big 'ol question mark to me.

Pre-posting edit: And more faults are rolling in, like warnings from the blind spot detection system that it can't communicate with ... well pretty much anything.

 

[jbooth]

We're apparently functional after charging the 12 V and resetting/reprogramming "some modules" (no info on which ones) which had lost communication within the car. None of this is a root-cause though, so I can't imagine that things are solved. Why did the 12 V go dead in the first place? How does the "electrical system drain; service required" message relate?

I'm waiting one more day for the car since they somehow hadn't noticed the "2nd key fob for job1s" that the social media team here noticed as soon as I messaged them. So a new fob is in the mail and hopefully they can program it tomorrow.

 

[Mach-Lee]

We're apparently functional after charging the 12 V and resetting/reprogramming "some modules" (no info on which ones) which had lost communication within the car. None of this is a root-cause though, so I can't imagine that things are solved. Why did the 12 V go dead in the first place? How does the "electrical system drain; service required" message relate?

I'm waiting one more day for the car since they somehow hadn't noticed the "2nd key fob for job1s" that the social media team here noticed as soon as I messaged them. So a new fob is in the mail and hopefully they can program it tomorrow.

Whole bunch of communications errors while programming is normal, the car sets about 20-40 codes so your FordPass will light up. Nothing to worry about, they get cleared out afterwards.

Make sure they do the BCM and GWM updates, that may help with battery drains.

 

[Luke]

I'm following this. My job1 car is also giving me daily warnings about 12 V battery drain. The dealer has no clue of what could be. They wanted me to bring my EVSE unit to test. Since coming back from the dealer I have not charged using my unit (I used an EA on the way home) . But I still Having daily warnings. Both on the app and the car dashboard.

 

[mwtechy]

I'm following this. My job1 car is also giving me daily warnings about 12 V battery drain. The dealer has no clue of what could be. They wanted me to bring my EVSE unit to test. Since coming back from the dealer I have not charged using my unit (I used an EA on the way home) . But I still Having daily warnings. Both on the app and the car dashboard.

Do you know what powerup version you're on?

 

[phil]

Everyone used to call my 1069 Cadillac a boat.

The Caddys built during the early years of the Norman Conquest were among the finest ever made.

 

[Luke]

Do you know what powerup version you're on?

Car in enrolled on early access, but it showing the OTA to fix the meeting issue. Update to address recalls 22S41 & 22S29

 

[dtbaker61]

The final of three jump starts was from a running 2003 Hyundai 4-banger. MME still wouldn't actually "start".

Also, interestingly, my ford pass won't start anymore. Just sits there at the Ford logo while "loading".

It seems very strange to draw a ton of power for the modules. I mean... I'm a software engineer and I build my own gaming PCs from parts. I have for long enough my first gaming PC (that I don't own anymore, but...) could legally drink. I have a UPS in my setup which isn't much more than a big old 12V lead-acid battery and an inverter. Sure if I'm gaming I'll have a 5-10 minute run time, but if it is just idle it'll be more like 30+ at a 200W draw. And that's a desktop PC with a power-hungry GPU, two displays, the router, dsl modem, desk lamp, ...

the typical tow truck 'jump pack' does not transfer enough energy into your 12v battery to run the 12v system very long. If you connect a running vehicle w jumpers, you probably need to leave it connected for a good 1/2 hour.... then get to a Ford dealership before it dies again if it is not getting charged properly from the dc-dc

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