Specialized Turbo won't stay on

The community bike shop I work with received a Specialized Turbo as a donation from a large local bike shop. I don't know its age, but it looks like the original red 2014-2015 models. It came with a beat-up charger labeled "RENTALS". The bike turns on when I poke the button on the downtube, and for a moment the display awakens and the headlight will turn on if I try it. But after a brief few seconds, it turns itself off again.

The charger switches to the red indicator when I plug it into the bike's charge port, but after a short time (minutes) it goes back to green as if the battery is full.

Is anybody here familiar enough with the Specialized Turbo to have a guess why it turns itself off immediately, rather than after putting it under load?

The battery is locked in place with a key that didn't come along with the bike, so I have to pick or break the lock to get the battery out for further examination. Also I have no reason to believe the battery will divulge any of its secrets to me or anybody who isn't the bike it was designed for.

I did some poking around, and cant' find any specifics about what's inside this system. However, it sounds like there is either:

a cell problem where one of the groups has high internal resistance, and probably very low capacity, so when charging starts, it quickly rises to HVC and the BMS shuts off the charging port. Then when connected to even a tiny load, it quickly drops to LVC and the BMS shuts off the output. (or tells the system to turn off, however this one works).


a BMS problem where either a sensor has a wrong output or the control circuit is not able to turn the output or input FETs on correctly (or at all). The bike powers on a little bit probably because of leakage current thru the FETs just enough to fill the controller's caps, which then when the system is turned on discharge and then it turns off when the controller hits it's LVC or dips below what it's LVPS can take for an input.


At least one of these bikes, not sure if it's the same model, had water damage to the battery so the BMS was damaged but the cells were fine, but the poster couldn't get any replacement parts (other than a whole battery). I don't think the specific symptoms were mentioned.

It's a medium PITA, but I think on that model you can disassemble the battery mount from underneath the bottom bracket. It's help in place by this crazy overcomplicated screw adjust assembly with a big threaded black plastic plunger for taking out battery rattle. Had to replace a guys key cylinder, and it came with official Specialized service instructions... so they're out there somewhere.

Voltron said:

It's a medium PITA, but I think on that model you can disassemble the battery mount from underneath the bottom bracket. It's help in place by this crazy overcomplicated screw adjust assembly with a big threaded black plastic plunger for taking out battery rattle. Had to replace a guys key cylinder, and it came with official Specialized service instructions... so they're out there somewhere.

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Thanks for this. It might be cost effective to replace the battery before reselling this bike, if that's the problem. Replacing the key lock may be part of that equation.

:thumb:

Can you turn on the bike while the charger is plugged in, and if so, does the charger switch to charging; and/or does the display stay on?

E-HP said:

Can you turn on the bike while the charger is plugged in, and if so, does the charger switch to charging; and/or does the display stay on?

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I haven't got the bike here with me, but as I recall, the battery and the display wake up, and then almost immediately turn off again, whether the charger is plugged in or not.

Its been about a month now, whats the story on the Specialized Turbo?

Chalo said:

E-HP said:

Can you turn on the bike while the charger is plugged in, and if so, does the charger switch to charging; and/or does the display stay on?

Click to expand...

I haven't got the bike here with me, but as I recall, the battery and the display wake up, and then almost immediately turn off again, whether the charger is plugged in or not.

Click to expand...

Good luck Troubleshooter !

I will guess that nice looking prominent lighted (?) " button " On/Off Switch maybe failed.

Because it's in a vulnerable location for any moisture, even a wet finger, and switches can be failure prone , or 'short lived'.
Mike