Tom L
Well-Known Member
- First Name
- Tom
- Joined
- Nov 5, 2021
- Threads
- 7
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- 391
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- 418
- Location
- Chippewa Falls, WI
- Vehicles
- 2018 Honda Clarity
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- Retired
Scoopman, sorry for your dilemma. I believe your analysis here is well drawn from the bits and pieces that MME owners have reported on this forum. I have read all the related postings and I think your summary is the most likely explanation of the contractor problems. We owe you a debt of thanks for your leadership.I would go a little further in speculation here. This is just my speculation, as I have had plenty of time enjoying the $7 gas prices driving around in a rental Ford Explorer to think about this. I'm not under NDA, just a gearhead who is also techie in software.
My feeling is that the GT and GTPE are wonderful cars that are fundamentally flawed because Ford made the decision to use the same battery pack and electronics for them as for the ER AWD.
When they made this decision, they also spec'd these parts to meet the ER AWD level of power requests and thermal tolerances, because they probably believed that the trim mix would much more heavily favor non-GT models than their (70%+ new to the brand) customers wound up ordering.
For the GTs and GTPE, Ford implemented a design philosophy of "derating" the power allowed on the car in order to keep the electrical power and thermals within the tolerances they thought would be acceptable. This strategy of proactively limiting the power that can be available, it was thought, would be effective enough such that Ford would not have to add costly engineering to the common pack used for both ER AWD and GT models to address the GTs.
Again speculating, but some of this engineering could have included bigger bus lines that deliver the electricity from the battery modules, better thermal management through more advanced cooling, and key actual temperature sensors at various points. That last item -- temperature sensors -- is probably the most glaring omission in my mind, because if you have actual sensors, you can limit power when the actual temperatures are getting too high, instead of inferring what the thermals are from simulations and modeling and then using them to proactively cut the power available.
I bet Ford is trying to do everything it needs to do with software modeling that figures out what that temperature should be from lab data (and maybe test mules they run around). But as we have seen, it is very tough with so little experience making EVs in the real world for Ford to have modeled this properly.
And so GT and GTPE owners suffer the consequences. Our cars derate themselves (the jail bars) at seemingly rando times to us, because this is what Ford predicts it must do to use the mid-range battery pack in a high-output application. So the car masquerades as a "PERFORMANCE" car when most of the time, Ford cuts some of the otherwise-capable power to protect its non-robust battery pack.
And most seriously, it has missed some fundamental training data for its model which caused key battery components to fail in spite of its extensive derating software design philosophy. I bet the software recall "fix" is just a further evolution of the derating to be more agressive in new situations they saw when contactors failed on the 300+ vehicles.
But as we've seen from my experience, it's really tough to cover all situations of vehicles in the real world with immature software.
Just ask Elon.
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