How often do typically cadence sensors typically fail on a new BBSHD?

sysrq

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After setting the slow start mode to 8 and stop delay to 10 ms the cadence sensor started working intermittently and then stopped working completely. It was working for a while when going back to old settings (4 and 100 ms) but then stopped. Only throttle works in PAS 1.
They said that it's fairly rare failure in other forums.
There might be no other choice but to forget about warranty and use throttle for hills only since then you will not have to worry about remembering to disable the PAS to avoid fast dangerous starts when pedalling from a stop
 
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Only throttle works in PAS 1.
Firmware versions out there will do that. There are threads on flashing and new firmware files. All here on ES
you will not have to worry about remembering to disable the PAS
After riding these motors since 2014 I can't imagine how that's dangerous. I seldom if ever leave PAS 1 and above. You can program PAS behavior and power settings.

I suggest you not just make changes willy nilly. It may be best to search out the numerous .el, controller files, for examples of successful settings.

PAS PCB failure is uncommon, but happens. In my support years we sold them but not a big item sold for failures. Like the plastic gear, IMO, much adieu about nothing. PCB quality can be flaky in BBSxx series motors but typically still work.

Are you certain it's not your settings?

The most common failures are in the first generation BBSHD. A weak rotor shaft has been upgraded.
1689897087592.png
 
Firmware versions out there will do that. There are threads on flashing and new firmware files. All here on ES

After riding these motors since 2014 I can't imagine how that's dangerous. I seldom if ever leave PAS 1 and above. You can program PAS behavior and power settings.

I suggest you not just make changes willy nilly. It may be best to search out the numerous .el, controller files, for examples of successful settings.

PAS PCB failure is uncommon, but happens. In my support years we sold them but not a big item sold for failures. Like the plastic gear, IMO, much adieu about nothing. PCB quality can be flaky in BBSxx series motors but typically still work.

Are you certain it's not your settings?

The most common failures are in the first generation BBSHD. A weak rotor shaft has been upgraded.
View attachment 336901
With original settings it doesn't work either so it might be something else.
Was trying to get the motor to kick in more softly and stop faster by using examples from this link.


There was a relatively tiny spark when trimming the wires after making sure they don't get shorted during cutting when soldering on the xt90 connector before testing it for the first time. I doubt it would have
caused delayed failure after four days of use since it was only a closed circuit for a current to flow with a capacitor. If that was the case there would be more reports about this since everyone is removing the Anderson connector.

Repeatedy plugging and unplugging the programming cable probably didn't cause any bad connection since the controller recieves the PAS levels (throtle works only in PAS1 and not 0).
 
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Firmware versions out there will do that. There are threads on flashing and new firmware files. All here on ES

After riding these motors since 2014 I can't imagine how that's dangerous. I seldom if ever leave PAS 1 and above. You can program PAS behavior and power settings.

I suggest you not just make changes willy nilly. It may be best to search out the numerous .el, controller files, for examples of successful settings.

PAS PCB failure is uncommon, but happens. In my support years we sold them but not a big item sold for failures. Like the plastic gear, IMO, much adieu about nothing. PCB quality can be flaky in BBSxx series motors but typically still work.

Are you certain it's not your settings?

The most common failures are in the first generation BBSHD. A weak rotor shaft has been upgraded.
View attachment 336901
So far looks like there is a poor soldering on a white wire.

Edit.
Now suddenly it started working in opened state. Was about to test the voltages on the sensor since there was a continuing on solder joints.
There could be possibility that the magnetic disc gets displaced too far away from a hall sensors since it's a bit loose.
 

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That could do it.
Now after putting it back together it was still working but after shortly turning on again cadence sensor doesn't work anymore.
Was tapping the solder joints but it didn't stop the sensor from working. Also reconnected the cadence sensor at the controller side.
 
Bummer.
You can test the sensor outputs with a voltmeter. You can do this on the controller side with everything hooked up. Measure the voltage on the grey and white wires while turning the crank slowly backwards. Put the meter negative on the black wire or the battery negative. You should see the voltage toggle from near zero to near 5 volts as you turn the crank.

The problem could be the sensor or could be the controller itself. If the sensor tests bad then replace or repair it. If it tests good it would point to the controller.
 
Bummer.
You can test the sensor outputs with a voltmeter. You can do this on the controller side with everything hooked up. Measure the voltage on the grey and white wires while turning the crank slowly backwards. Put the meter negative on the black wire or the battery negative. You should see the voltage toggle from near zero to near 5 volts as you turn the crank.

The problem could be the sensor or could be the controller itself. If the sensor tests bad then replace or repair it. If it tests good it would point to the controller.
I thought there is no point to measure the hall sensor voltage when it was working when opened since you need three hands to do it without soldering.

I think I will disable the cadence sensor for good in the app since I feel like the cadence sensor is inherently unsafe due to possibility of starting in too high of a PAS level. After setting up the throtle with 8 current levels to get used to it will use it for pulse and glide technique when necessary and pedal during the rest of the time.
 
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I rode for a long time with my PAS sensor disconnected. I found it unsafe to use on technical trails. I have it working again, but rarely use it.
 
I rode for a long time with my PAS sensor disconnected. I found it unsafe to use on technical trails. I have it working again, but rarely use it.
Seller responded and said that I should check the spoke magnet and speed sensor for pinched wires to make the cadence sensor work again
 
Not sure about that. If the speed sensor isn't working, the speed display will stay at zero and the display will turn itself off after a few minutes. There's a little red LED on the speed sensor you can check to see if it blinks when the magnet passes by.
 
Not sure about that. If the speed sensor isn't working, the speed display will stay at zero and the display will turn itself off after a few minutes. There's a little red LED on the speed sensor you can check to see if it blinks when the magnet passes by.
Also was surprised about that kind of answer from a local seller. There wasn't any problems with speed sensor to begin with.
 
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