Mach-E Recall & Stop Sale ...

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OldManCan

Well-known member
Joined
Nov 19, 2021
Messages
300
Seems like Mach-E is having its Bolt moment... Let's hope they sort this one out quickly for the safety of many Mach-E owners and their passengers out there.

https://insideevs.com/news/592075/ford-mustang-mache-safety-recall-stop-sale/

[Mod edit: removed Facebook tracking from the link]
 
The Good (tm) news: the battery pack is not involved
This issue: sounds like the contactors are not up to spec

The OTA is (I presume) going to nerf max current. That should go over well with the owners :roll:
 
No, it's not....and its personally upsetting
As an EV owner, I have to say this sort of thing makes ALL EV companies look bad. As an engineer, it makes me wonder how this stuff gets through the QC process...especially with companies that (I assume) have large, well-funded development teams (like Ford/GM/etc).
 
If the problem is the build quality of the contactors - as opposed to the rated current handling ability - then they will likely fail even with max current restricted. It will just take a bit longer.
 
LeftieBiker said:
If the problem is the build quality of the contactors - as opposed to the rated current handling ability - then they will likely fail even with max current restricted. It will just take a bit longer.
Unless by "build quality" they mean instead of using particular sized contacts they cheaped out and used smaller contacts, in which case they've effectively derated the contactor so in that case limiting the max current is the ticket.....until they can replace the contactors.
 
Stanton said:
As an EV owner, I have to say this sort of thing makes ALL EV companies look bad.

Totally agree. This will be a set back across the board as perceptions are hard to unset. Hope there is some learning in this for the whole industry.
 
Unless by "build quality" they mean instead of using particular sized contacts they cheaped out and used smaller contacts, in which case they've effectively derated the contactor so in that case limiting the max current is the ticket.....until they can replace the contactors.

This is not my area of expertise but I can think of a lot of other factors that could affect the lifetime of the contacts:

material composition, flatness, finish, parallelism, contact force (vs vibration), contamination, cleanliness, etc.

EV's are still a relatively new technology compared to gas guzzlers and there are sure to be some learning curves to climb as they become more popular and manufacturers start trying to take cost out the designs.
 
GM has been building garbage cars for years now, so this is really just par for the course for domestic manufacturers. Feel bad for owners, but I wouldn't even consider buying a brand new GM or Ford model as their reputations precede them.

The smart move is to wait at least a couple of years for any major design problems to reveal themselves before considering any new model. Same for any major changes to an existing model. Even Toyota doesn't have a perfect record.
 
Stanton said:
No, it's not....and its personally upsetting
As an EV owner, I have to say this sort of thing makes ALL EV companies look bad. As an engineer, it makes me wonder how this stuff gets through the QC process...especially with companies that (I assume) have large, well-funded development teams (like Ford/GM/etc).

Rush to market. They knew...
 
alozzy said:
The smart move is to wait at least a couple of years for any major design problems to reveal themselves before considering any new model. Same for any major changes to an existing model. Even Toyota doesn't have a perfect record.

^^ This! On that note the venerable LEAF is the more sure proof choice for now. I will certainly wait for 2nd gen Ariya or what ever comes next after my LEAF.
 
My guess is that the modified firmware will build a model of the contactor's temperature; a fancy way of saying they make an informed guess. When the guessed temperature gets too high, then they limit max current (either discharge or charge current) and pop up a message saying that due to an over-temperature situation, maximum power is temporarily reduced.

So then you can still do a few "wide-open pedal" runs to impress your friends, just not all day. As long as the model is reasonably accurate, it should prevent excessive contactor wear. No doubt in the fine print for the 500A contactor (a wild guess) will be that this is subject to a "typical" duty cycle. Hot footed drivers can exceed this duty cycle without realising it. So it's not really incompetence on the part of the original designers, more a lack of foresight. It's hard to foresee every co-ordinate a design space will hit in real life.

Sure, a really experienced designer would have thought "wait, I bet there will be some more fine print on this" and gone looking.
 
^Very interesting. I assumed all the wear would be during opening/closing operations but after reconsidering, electro-migration might be the bigger problem.
 
coulomb said:
My guess is that the modified firmware will build a model of the contactor's temperature; a fancy way of saying they make an informed guess. When the guessed temperature gets too high, then they limit max current (either discharge or charge current) and pop up a message saying that due to an over-temperature situation, maximum power is temporarily reduced.

So then you can still do a few "wide-open pedal" runs to impress your friends, just not all day. As long as the model is reasonably accurate, it should prevent excessive contactor wear. No doubt in the fine print for the 500A contactor (a wild guess) will be that this is subject to a "typical" duty cycle. Hot footed drivers can exceed this duty cycle without realising it. So it's not really incompetence on the part of the original designers, more a lack of foresight. It's hard to foresee every co-ordinate a design space will hit in real life.

Sure, a really experienced designer would have thought "wait, I bet there will be some more fine print on this" and gone looking.

A rating of 500A is very likely on the low side. If the design engineer did a worst case analysis with a 25-50% over-rating,
the contactor most likely should be rated on the low side at 1500 amps. The Tesla Model S easily reaches 1300 amps;

https://teslamotorsclub.com/tmc/threads/using-tm-spy-to-see-model-s-data.63051/#post-1381783
 
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