LectricGT

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Yes, I understand all that.

My question is: Does anything else cause heat, or a bug that caused something to draw/discharge power when it shouldn't have been, to the contractors which could cause them to have been at a higher starting temperature, therefore making repeated WOT events and/or DCFC charging put the contactors in the "danger zone" temp wise? Whereas if this "something" wasn't drawing/discharging power, the starting temp would have been lower thus the max temp created from WOT events and DCFC charging would be lower, too.

This contactor (electromechanical switch) connects and disconnects the HV battery from the car. Anything that charges or discharges the HV battery will contribute in some way to heat developing in the contactor. The A/C compressor and cabin heat technically would contribute, but their contribution is dwarfed by the drivetrain, and these loads appear to be already taken into consideration with the drivetrain power limiting algorithm, anyway.

The other side of the equation is how well the contactor can sink and dissipate the heat that is created. Warmer ambient temperatures, warmer battery all work against this dissipation to some extent. Overheating would seem to be more probable on a really hot day than a cold one.

Another thought that came to mind was how the initial temperature of a calculation was seeded, whether by something such as a battery temperature sensor or making an assumption (e.g. always starting with 30Ā°C), and does this calculation stop once the car is turned off. If it does, then conceivably the contactor temperature could be pushed into the danger zone by turning the car on and off frequency (think very short trips) and doing those regular hard pulls. But this case seems rather remote since it would involve a rather specific and unusual operating behavior.
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ChuckA

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I had an open appointment for today to install 21P22 so I had them do 22S41 while the car was at the dealer. Both done successfully. They had the car for 6 hours, but only .6 hours were for 22S41.
 

LectricGT

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The only flaw Iā€™ve seen is a 500a rated relay in a place that flows 750a or higher at some points for an extended time. Perhaps they misjudged the quantity of lead feet?
More like grossly underestimated the current carrying duty cycle of the contacts. Very crude, back of the napkin math says that full acceleration in a GT is over 1000 amps. A 500 amp contactor will do that, but not for very long. Even shorter once it has been "exercised" a couple of times above 500 amps immediately prior to that.

Do you know whether this is the actual contactor rating? It seems to ride that edge with a maximum DCFC rate of 150kW.
 

ZuleMME

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More like grossly underestimated the current carrying duty cycle of the contacts. Very crude, back of the napkin math says that full acceleration in a GT is over 1000 amps. A 500 amp contactor will do that, but not for very long. Even shorter once it has been "exercised" a couple of times above 500 amps immediately prior to that.

Do you know whether this is the actual contactor rating? It seems to ride that edge with a maximum DCFC rate of 150kW.
https://www.macheforum.com/site/thr...icture-of-the-hv-contactors.19114/post-452712
 

breeves002

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Recognizing that, but with all due respect, you do not own a GT or GTPE trim.
GT PE here no difference Iā€™ve noticed. I updated this morning. 90 degrees here did some highway driving then tested. 5 second power limit exists still, acceleration feels the same all speeds as it did before.
 


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Are you saying that the brakes are acting differently/smoother after this recall update? Or did you separately have the brakes looked at and adjusted by the service techs?
Yes the brakes are way smoother now in my opinion from the transition from regen to actual friction brakes right before the car comes to a complete stop. You canā€™t tell anymore. At least with mine. Before this update there was a noticeable change when it happen right before my car would come to a compete stop. No more now. Woot
 

ZuleMME

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Yes the brakes are way smoother now in my opinion from the transition from regen to actual friction brakes right before the car comes to a complete stop. You canā€™t tell anymore. At least with mine. Before this update there was a noticeable change when it happen right before my car would come to a compete stop. No more now. Woot
Iā€™m certainly noticing the regen seems different. Stronger perhaps? That could simply be that it reset and has to relearn my driving style.
 

jamelski

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Iā€™m certainly noticing the regen seems different. Stronger perhaps? That could simply be that it reset and has to relearn my driving style.
No clue. Just happy that itā€™s gone was so Annoying it would be like cruising to stop and then the moment they went to friction it was like an annoying jerk stop vice chill roll to stop lol. I noticed the update says that the ABS module can be updated Iā€™m assuming mine was because itā€™s 1000 times better now.
 

Ajax

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Yes, I understand all that.

My question is: Does anything else cause heat, or a bug that caused something to draw/discharge power when it shouldn't have been, to the contractors which could cause them to have been at a higher starting temperature, therefore making repeated WOT events and/or DCFC charging put the contactors in the "danger zone" temp wise? Whereas if this "something" wasn't drawing/discharging power, the starting temp would have been lower thus the max temp created from WOT events and DCFC charging would be lower, too.
Piggybacking on this, is there anything folks can do who can't get the recall and have long trips planned that require regular DCFC, say 3-5x/day? E.g. stop vehicle and wait a few minutes before and after DCFC, don't charge past 80%, etc. Or use Whisper/Engage instead of Unbridled.

I can't get the recall until 7/11 and have a big trip coming up this weekend that I really want to take and renting/flying/taking Amtrak aren't options for various reasons I won't get into here.
 

Ajax

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I called my dealer and the service lady said that they don't have the parts in stock. šŸ˜‚

I told her that it was a software update and she responded with, "we don't have the software yet". šŸ¤”

What a clown show.
All of the dealers in the Twin Cities are clown shows. Took me 6 weeks and a combination of 2 dealers in MN to get Blue Cruise alone installed, and it wouldn't have happened without help from @Gimme_my_MME (šŸ™Œ). I effectively paid over $1k for Blue Cruise in lost time and monthly payments that went to a car sitting in the service bay/dealership parking lot. I am seriously considering using my sh*tty work Windows laptop just for FDRS and doing this on my own going forward.
 

Shayne

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We know that 0.6% of MMEs sold in the US have had this failure so far. The initial recall from Ford stated that due to variability in manufacturing, some of the contactors were not robust enough. Some members have guessed that between 1% and 5% of contactors may be faulty and eventually fail. It is possible that the software fix monitors the resistance in the contactors and will detect when they are about to fail. Then it will reduce power to the contactor and warn the driver so that they can drive to a dealer to get a replacement part, rather than experiencing a failure that leads to a car stuck somewhere that won't start. In this scenario, the only time this software affects the car is when it detects an upcoming failure in the contactor. Between 95% and 99% of MMEs will never have a failure in their contactors, so they will never be affected by this software update. Maybe, Ford has not specifically said what the software update is doing.
Were did you get that only some of the contacts are not robust enough? I understood all vehicle were fitted with certain contacts and none of them are robust enough. That this is a installed/design problem not random defective parts. The recall certainly does not read as if 1 in 200 are defective it says they are not robust enough for there intended purpose under certain conditions. It then lumps every MME built to date (up to may 24) into this recall. Was not my opinion that there are only a few flakey ones. If so they would have definitely came out and said that as that is a whole lot better than saying the part installed is not robust enough and it effects all MME's.
 

Neil4Real

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Were did you get that only some of the contacts are not robust enough? I understood all vehicle were fitted with certain contacts and none of them are robust enough. That this is a installed/design problem not random defective parts. The recall certainly does not read as if 1 in 200 are defective it says they are not robust enough for there intended purpose under certain conditions. It then lumps every MME built to date (up to may 24) into this recall. Was not my opinion that there are only a few flakey ones. If so they would have definitely came out and said that as that is a whole lot better than saying the part installed is not robust enough and it effects all MME's.
Ford said it is due to a variance in manufacturing. Because of that, it would be impossible to identify specific VINs that received one of these deficient parts.
 

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Ford said it is due to a variance in manufacturing. Because of that, it would be impossible to identify specific VINs that received one of these deficient parts.
Link please. Who develops software for all due to a few with defective parts just makes no sense. What they were forced to say in the recall is where my speculation remains.
 

ZuleMME

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The part is rated for 500 amps continuous. DCFC hits that or lower. But heats it effectively to full temperature. Then you get in and drive sanely and it should be fine. If you then get in and pull 750A constantly (Premium) or 900A (GT) etc you will QUICKLY exceed itā€™s design capactity and risk failure. Ford likely originally expected this and had some dial back programmed in. I suspect this update makes it engage that faster. Thatā€™s all.
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