Flux linkage detection failed (Motor detection)

ok yes, might have found the issue, when I plug/unplug one of that 4.0mm connector^ it fixes the problem. if I plug in the single cable back in, it makes the motor brake. I’ll try to resolder that one.

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Excellent find! Let me know how it goes my dude.

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The problem doesn’t seem to be from the outside, everything seem to work find there. Perhaps something in the inside is wrong? The cable that fucks everything up is that middle one^.


Hmm after this, I just can’t have it detect the flux linkage.

Looks like your bullet connectors are not insulated.

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Test for continuity on your multi meter and do all combinations of phase wires

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Yeah, I was going to insulate them at the end. After having done everything.
Any idea why is there that error?

Edit: when turned on, it just brakes without any input, I don’t know why is it doing this behavior.

If the connectors touch, you have a short and the motor doesn’t turn very well. The motor will brake and create max braking torque.
If you run it like that, any touch of the connectors will probably kill the ESC.

I’m trying to run them untouched at the moment. But it still brakes a lot. I didn’t add that cover yet because I need to take them in and out of a tight space where a cover won’t go through.
Now even if they aren’t touching each other, the (middle wire) is applying full brakes at the motor, if I ever take that one out, the wheel could spin normally, but when all 3 phase wires are connected it just can’t.
And in the vesc tool it just won’t let it spin/ detect foc.

In that case your esc is damaged.

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I had the same issue, plugging in all 3 phases and motor would brake. Two phases and free spin, I think I isolated it to certain phases but that didn’t really matter…

Turns out I had a bad DRV, once that was replaced, I resoldered all the phase wires and cleaned up the flux real good off the board and everything works again.

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spin resistance just means that there is a short somewhere in the phase wires. If the short isn’t external, then the ESC fets are blown in open, essentially same thing as a short circuit. If the motor spun fine before you ran motor detection and it only happened after, then it could’ve been caused by a short during motor detection. If it was like that before you ever powered on the ESC, then it was defective from factory.

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The bottom left transistor looks a bit burned, is that just dirt?

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You probably have a shorted FET in your ESC. Possibly caused by not insulating the phase wires. If this is true, that ESC is no longer usable.

You can verify this theory by switching the motors, connect the left motor to the right ESC et cetera. If the motor that’s malfunctioning switches sides, then it’s an ESC problem.

You can also test the motors while unplugged from the ESC.

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Yeah, I’ve switched my esc with my motors, and it is indeed a esc problem. :confused:
Not sure how to fix this.

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Measure the mosfets metal surface to gnd and then plus pole of the battery (resistance).
One or two FETs will probably bring up different results than the other FETs. That’s the blown FETs that need replacing.

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Hello!

Does this mean this these 3 mofsets are fucked and need to be changed?

Did you ever resolve this issue?

I believe I have the same or similar issue. In my case, FOC motor detection spins up the motor but there’s resistance when I go to test fwd/rev and finish setup. In BLDC, motor spuns but it’s rough. Any help is appreciated as I’m out of ideas.

What ever happen with this?