brose drive S display says "no motor"

fm4711

fm4711

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Hi!

My wife's Specialized Como 4.0 has a Brose Drive S, which stopped working. On power-up, it shows "no motor" on the TCD.
All wires have been checked for contact (by both me and the shop), they say get a new motor for $$ (out of warranty after 2.5 years).
To me, feels like a sensor problem b/c bike hasn't been used that much, and when I opened the motor, it's clean (no water), belt and planetary gear is in great shape, main board shows no burned out components (very clean). Did anypone have this before? Maybe the torque (ring) sensor or hall sensor?

I hear that replacing circuit board is no option since it's custom programed not just for Specialized setup but also to fab differences in rotational/gear elements, if that's true?

Might have to send it off from NC to TN to Michael for repair, or even order a new one for $$ unless someone has a hint.

BTW, I did measure resistance over 3 motor contacts, they are identical.
Is there a way to test torque/hall sensor w/ multimeter as well, maybe even w/o removing from circuit board?

Any help welcome.
 
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This may be way off base but have you removed the battery and cleaned the connections really well. I don’t know if it was the motor resetting from the battery removal or the cleaning but I had the same error that cleared after I did this.. make sure to really really clean out the pin hole connectors in the charging door.
 
Interesting thought, thanks for the input, here's what I did:

Battery connectors are clean but I'm a bit puzzled by the voltage readings:
Removed battery, measured 6 pins as: ground, 38, 39, 28, 0, 41V. Are these readings of cells in a parallel circuit? Are there 4 such cells or 5? The 0V readings is strange.

Battery to motor connector also has 6 pins. 4 of them show connection (incl. main ground and +41V to drive motor), but two other pins are *not* connected from battery terminal to motor terminal.

Does anyone have any data on this?
 
Just thinking out loud here.... Motor may not like the 28v cell bank. Do you have another battery to test with? If you're testing with a multimeter, we both know w/o a schematic with specs, it's pretty much a guess at what the values should be. FWIW, I'm guessing the battery is 4 42v banks in parallel to get the wattage required to run the motor.
 
No other battery, even the shop doesn't have one. Unless someone reads this and does me a big favor to measure their Como 4.0 battery, I'm shit out of luck and will have to try a new motor first. The 28V does worry me as well though. Called Specialized, they are of no help, they just go down their checklist, and electronics is not their thing. Just full replacements of motor and battery, one at a tim, is their service solution.
 
Quick google search shows battery might be the Specialized U2-710. Yes? FWIW, I did a very fast search and found some internet info but no pin voltages. You might want to put the googl search engine to work...
 
fm4711 said:
Hi!

My wife's Specialized Como 4.0 has a Brose Drive S, which stopped working. On power-up, it shows "no motor" on the TCD.
All wires have been checked for contact (by both me and the shop), they say get a new motor for $$ (out of warranty after 2.5 years).
To me, feels like a sensor problem b/c bike hasn't been used that much, and when I opened the motor, it's clean (no water), belt and planetary gear is in great shape, main board shows no burned out components (very clean). Did anypone have this before? Maybe the torque (ring) sensor or hall sensor?

I hear that replacing circuit board is no option since it's custom programed not just for Specialized setup but also to fab differences in rotational/gear elements, if that's true?

Might have to send it off from NC to TN to Michael for repair, or even order a new one for $$ unless someone has a hint.

BTW, I did measure resistance over 3 motor contacts, they are identical.
Is there a way to test torque/hall sensor w/ multimeter as well, maybe even w/o removing from circuit board?

Any help welcome.
Click to expand...
The ring sensor is not plugged in properly
 
It turned out to be a motor failure $750 later. I opened the faulty motor, no sign of blown parts on the circuit board and clean as a whistle. I can't believe specialized didn't cover more of the cost as this motor with low usage clearly was a lemon. Tough luck, no more specialized will be purchased by me anymore.
 
I can guarantee its the two pins that plug into the ring sensor. No motor found I think a lot of these motors from the factory are not plugged in properly.
 
When you open the motor and looked at the circuit board. Did you unplugged the ring sensor? It’s probably not plugged in properly.
 
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