Maquis
Well-Known Member
- First Name
- Dave
- Joined
- Dec 21, 2020
- Threads
- 34
- Messages
- 5,688
- Reaction score
- 8,068
- Location
- Illinois
- Vehicles
- 2021 Mach E4X, 2023 Lightning Lariat ER
Right - the EVSE sets the "duty cycle" (ratio of positive pulse width to negative pulse width) and the car determines the voltage by loading the signal. It sounds like the problem may be related to the car improperly loading the signal resulting in improper pulse voltage.Been a while since I looked at the J1772 signals. I was just googling to find a chart for the post that asked about the duty cycle for 40A, and then I saw this slide about the various peak waveform voltages showing "state". I do not remember where someone mentioned a low voltage, but here it looks like there are several normal "pilot high" voltages below 12V:
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Now, the ultimate reason for only some cars (seemingly concentrated in NE IL) exhibiting this problem is the real conundrum!
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