Levo Gen 2 2020 Levo Diagnostic Help

[Dmurphy48]

I have a 2020 Levo comp. Everything worked fine through this past season. I haven’t touched it in a month or so (I am in Colorado and it is ski season) and decided to do some maintenance which included full tear down, bearing replacement and cleaning. I did take the motor out and put everything back in per the manual and per pictures I took before disassembly. All of the wire connections are reinstalled the way I found them. I am getting nothing when trying to power on the bike. I checked the power cable and on one of the small pins I did not have continuity so figured I solved the riddle. Just got back from the shop where they checked the battery (everything in good health) and I picked up a new cable. Bike still is completely dead. I checked the speed sensor wire and TCU.wire and at least they do not feel pinched or bound up. I will check continuity this weekend to keep hunting for issues. Any other thoughts. I know there are a lot of posts and most are solved with a new power cable. I can’t find a diagnostic procedure to eliminate things and am looking for some help on how to approach this.

 

[crazyethnic]

Have you charged the TCU they have a built-in power supply that might need charging?

 

[Mikerb]

Firstly did you power up the bike before starting your teardown?
If it all worked OK then it seems most logical that something is wrong with your rebuild......if you did not check prior to teardown the bike may have become faulty during the period of non use and discharged TCU battery maybe the cause....easy to change anyway to eliminate that possibility.
Assuming by "bearing change" you also worked on pivot bearings it is possible to damage the speed sensor cable at the point it exits the chainstay......and if you are confident you have remade all connections properly, then the next suspect would be a cable...the speed sensor cable being the most likely. Personally if replacing that cable I would run it externally since the internal routing not only risks damage to the cable where it exits the chainstay but the cable actually damages the chainstay by enlarging the exit hole.

 

[Dmurphy48]

Thanks for the thoughts. I did not check the bike before tear down. I pretty much rode it on 12/4/22 and put it away and did not touch it until tear down a week or so ago. It worked fine when I rode it and had worked fine all summer. I replaced the TCU battery (that was a fun job) and still no power. I then pulled the TCU to motor cable out and checked continuity on all 5 pins and two are bad (orange and green wires) so that is likely my next replacement although this just seems odd that two separate cables magically went bad sitting in my garage since 12/4. If that doesn’t fix it my only choice is a new TCU. I am not sure if the speed sensor matters to power up the bike but regardless I don’t know how to check those wires with a voltmeter as the magnet connector covers up the connections. The wires look okay from visual inspection. That is a $60 cable so I will wait on that until last. Not sure on the TCU cable but I am sure it isn’t cheap.

 

[Mikerb]

I dont know if these are any help? The first describes how the Levo powers up. The second is a basic test of the only component required to power up ( power up but not get drive from the motor, to get drive the TCU also has to recieve a signal from the speed sensor and torque sensor except for the walk assist...hence this form of test).

 

[fletch]

Cant help with your issue but i would suggest if you can swap the tcu with a known good one to rule that out or not, anyway if you do need a new tcu use the spesh assistance programme and you will get 30% off which sweetens the pill.

 

[Mikerb]

I dont know if these are any help? The first describes how the Levo powers up. The second is a basic test of the only component required to power up ( power up but not get drive from the motor, to get drive the TCU also has to recieve a signal from the speed sensor and torque sensor except for the walk assist...hence this form of test).

View attachment 104760 View attachment 104761

Nowhere does the tech manual actually provide a proper wiring diagram so it could be that the 2 wires in the TCU cable that failed your continuity test may well be the signal circuit from the TCU which is an open circuit until the TCU button is pressed ( refer to first photo).

 

[Dmurphy48]

My local shop where I bought the bike was pretty helpful and let me swap out parts to isolate it to the cable between the motor and TCU. Luckily that cable was only $20. Luckily these bikes only have a few things to check, 3 wires, the TCU and then the motor itself. For future information you don’t need the speed sensor cable to power up the bike.

 

[Mikerb]

My local shop where I bought the bike was pretty helpful and let me swap out parts to isolate it to the cable between the motor and TCU. Luckily that cable was only $20. Luckily these bikes only have a few things to check, 3 wires, the TCU and then the motor itself. For future information you don’t need the speed sensor cable to power up the bike.

Ah...well done. Do you suspect you damaged that cable during your teardown? Yes the speed sensor will not stop the TCU powering up but if it is faulty the TCU will show one of its fault codes ( red/blue flashing) and there will be no drive from the motor.

 

[Dmurphy48]

I guess I had to damage it during tear down. I should have used a set of pliers to re install it as when you use your hands you can smash the wires a bit pushing it into the female connector. Lesson learned.

 

[Binhill1]

I guess I had to damage it during tear down. I should have used a set of pliers to re install it as when you use your hands you can smash the wires a bit pushing it into the female connector. Lesson learned.

Don't like putting in and out small wires like that . I couldn't get it by hand but long nose pliers managed.

 

[Mikerb]

Don't like putting in and out small wires like that . I couldn't get it by hand but long nose pliers managed.

plug connector pliers make the job easy, better grip than long nose pliers which ensures you do not compress the connector which can dislodge the pins. Either way grabbing the wires is a no no!!