High voltage battery warning(non hvbjb)

[Wipeout]

Hi all,

2022 GT built Feb ‘22. Has about 10k miles on it. Got the high voltage warning August 3, dropped off at dealer then.

Received car back Sept 1. Unfortunately, it looks like the little power limiter bars are near maxed despite high state of charge and either not moving or going just a few mph. Similarly, the acceleration does indeed feel limited.

While I’ll likely be bringing this to the dealer again, I’m hoping for some additional input. My initial 29 day stay at the dealer consisted of me calling every 2-3 days trying to receive any update(what’s the issue? Eta? Etc). It took about 2 weeks of having no call backs or texts from the rep before I asked for the manager, at which point the rep materialized and gave some nonspecific answer of an electrical part needing replaced. I had assumed it was the hvbjb and gave it more time. Similar to above, i heard no news(despite trying) until the
day of when I could pick it up.

Attached is the service receipt + limit photo, which was the same when it was >80% as well.

 

[Just Lurking]

My initial 29 day stay at the dealer consisted of me calling every 2-3 days trying to receive any update(what’s the issue? Eta? Etc). It took about 2 weeks of having no call backs or texts from the rep before I asked for the manager, at which point the rep materialized and gave some nonspecific answer of an electrical part needing replaced.

That is unacceptable. I'd find another dealer, if possible.

Not sure about your jail bar issue, though. What's the weather like where you are, any extreme temperatures? Was the car driven extremely hard?

 

[VaporTrails]

Jail bar implies to me that the vehicles battery sensors are detecting a thermal issue and limiting motor inverter engagement. The HVBJB is on or off. The only thing the car can do is reduce the inverter draw. So…either the coolant loop isn’t cooling or the thermal sensor(s) is not plugged-in. Both seem likely to be HVBJB installation errors. If you are getting jail bars, there should be a sea of cars in your rear view mirror in a series of events generating enhanced G-forces. Under no circumstances should sauntering around town on errands be generating this.

 

[Wipeout]

That is unacceptable. I'd find another dealer, if possible.

Not sure about your jail bar issue, though. What's the weather like where you are, any extreme temperatures? Was the car driven extremely hard?

70s, no hard driving. Basically just turning it on and sauntering around town like Vaportrails said haha.

I’m going to try a different dealer but my impression is it’ll be the same EV tech that covers this area? Maybe that’s changed

 

[heisnuts]

70s, no hard driving. Basically just turning it on and sauntering around town like Vaportrails said haha.

I’m going to try a different dealer but my impression is it’ll be the same EV tech that covers this area? Maybe that’s changed

EV techs are usually dealer specific since each dealer is independently owned and operated and they are the one employing the EV tech.

 

[Wipeout]

Jail bar implies to me that the vehicles battery sensors are detecting a thermal issue and limiting motor inverter engagement. The HVBJB is on or off. The only thing the car can do is reduce the inverter draw. So…either the coolant loop isn’t cooling or the thermal sensor(s) is not plugged-in. Both seem likely to be HVBJB installation errors. If you are getting jail bars, there should be a sea of cars in your rear view mirror in a series of events generating enhanced G-forces. Under no circumstances should sauntering around town on errands be generating this.

After some more time, this really feels like the answer. It’s basically as if the powers limited when the SVS warning shows, just with no warning. Sigh. Waiting for business hours to try BEV team(again) lol

 

[Wipeout]

Update: Got the car back from alternative ford dealer in my area after 9 days.
They replaced LK9Z*10C666*BRM … I think this is the hvbjb?

The second dealer also found out that the coolant loop was clamped from the initial repair still…. I’m worried there may have been some sort of permanent damage to the car :/
@VaporTrails

 

[VaporTrails]

They replaced LK9Z*10C666*BRM … I think this is the hvbjb?

Yes, indeed it is. You have the 2022? They replaced the HVBJB with the new part you just had installed. I think starting with the June 2022 assemblies. Hopefully you won’t have any further issues! The pre-June junction boxes were sometimes affected even with a slow trot.

 

[Wipeout]

Yes, indeed it is. You have the 2022? They replaced the HVBJB with the new part you just had installed. I think starting with the June 2022 assemblies. Hopefully you won’t have any further issues! The pre-June junction boxes were sometimes affected even with a slow trot.

Ya, built Feb 2022. I saw it’s just the connector portion now not the whole rig, cool. Fingers crossed.

Need to let some regional manager know about the initial dealership. Left my coolant loop clamped and my spouses damaged… lol

 

[Mach-Lee]

Ya, built Feb 2022. I saw it’s just the connector portion now not the whole rig, cool. Fingers crossed.

Need to let some regional manager know about the initial dealership. Left my coolant loop clamped and my spouses damaged… lol

How long was it clamped for? Driven at high speeds?

 

[Wipeout]

How long was it clamped for? Driven at high speeds?

5 days. Yes. Longest trip of maybe 30 minutes at highway speeds. Whatcha thinking?

 

[BigMach-E]

Hmmm, I don’t know if there is such a thing as malpractice for mechanics…but…

 

[Mach-Lee]

5 days. Yes. Longest trip of maybe 30 minutes at highway speeds. Whatcha thinking?

That appears to be the coolant hose that leads to the rear inverter and motor. If that was blocked, it's possible the rear inverter and/or drive unit overheated while driving with the clamp in place. That would have caused the power limit to appear. I'm not sure how robust Ford's FMEM is for complete coolant hose blockage, but it's possible the inverter or drive unit was damaged and could fail early. It's probably a "wait and see" situation.

I've marked the location of the clamp on the coolant piping diagram with a magenta X:

 

[VaporTrails]

The MME has an oil to glycol heat exchanger on the motors. (Yes, MME’s actually do have oil.). It is entirely possible this loop kept the motor cool _enough_ during your trips to avoid damage. I have no idea how high those thermal limits might be. Unlike an ICE, this oil is not experiencing detonation temperatures or acidic combustion by-products, so likely would last a very long time. I need to dive in to see if the control electronics get temperature from the glycol loop or from a sensor in the motor itself. (Probably both)

 

[Mach-Lee]

The MME has an oil to glycol heat exchanger on the motors. (Yes, MME’s actually do have oil.). It is entirely possible this loop kept the motor cool _enough_ during your trips to avoid damage. I have no idea how high those thermal limits might be. Unlike an ICE, this oil is not experiencing detonation temperatures or acidic combustion by-products, so likely would last a very long time. I need to dive in to see if the control electronics get temperature from the glycol loop or from a sensor in the motor itself. (Probably both)

That heat exchanger is #13 in the diagram. But with the clamp on the line there would be no flow on the glycol side, so the heat wouldn’t be able to go anywhere. The MOSFETs in the inverter can overheat in only seconds with no glycol present in the water block. It’s analogous to running a computer without any heat sink on the CPU chip.

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