- Aug 9, 2020
- Reaction score
- Northern Ontario Canada
- 2021 MME4x Prem
You and @smoke20 sound like two sides of an old discussion. Once it is part of the design it is inherent in them all. My first failed hvjb they had no idea what was going on. It took some time finally pointing to stuck open contacts followed by an extended wait for the part. The second all the bells and whistle went off with TSB's and everything.As an engineer with related experience, I can tell you that heat removal should not be required in a properly designed contactor. The welding is indeed due to arcing which is caused by either improper intermittent contact or too little surface area of contact for some reason. Also, while the bus bars do conduct heat, the thickness and other dimensions are primarily designed to keep electrical resistance down to minimize production of heat. It does seem to me that this problem is a design flaw. It is apparently a subtle one that took thousands of vehicles in real world conditions before it was even identified. Just one of the drawbacks for early adopters like all of us!
Sounds like thicker bus bars are a no brainer to throw in even if not the complete fix. Don't really care what fixes it but could use the saga over. Engineers should know it is best to fix the problem professionally and point fingers afterwards. This one has gone on way too long with a poorly engineered software bandage fix which was of course no fix at all for under designed hardware.
Similar type of software bandage has again been dropped on us early adopters. We should have our L2 charging speed fixed also without Ford being forced to fix it. I don't want a defective overheating charging port beside my home; if it is throttled or not. The sagas of software trying to fix design defects in their hardware continues.