Focus Jam2 Factory won’t turn on and is not charging

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
Hi all,

I’m owning a Focus Jam2 from 2017 equipped with a Shimano E8000 system.

Yesterday I’ve installed a new handlebar and therefore disconnected and re-attached the wires from the assist switch to the display unit and the wire from the drive unit to the display (put back in same display ports).

To my surprise the bike didn’t turn on. Also, when charging, the charger led indicator blinks red after 30 seconds, so it’s not charging.

I’ve then also tried to turn the bike on with my TEC pack external battery, but without succes.

Does anybody has any idea about the possible cause of this issue?

Thanks!
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
thanks! @bluesurf989

It indeed looks like a similar issue. It’s annoying that you need to take the whole drive unit off, and open the battery casing in order to ‘reset’ it. It doesn’t seem so ‘easy’ to me, but it should be doable - I’ll give it a try during the weekend.

P.s. Do you know what the underlying issue could be? As far as I know I didn’t make any mistake when reconnecting the wires, after changing the handlebar.

Did the issue occur randomly in your case? And did it came back after the reset?
 

bluesurf989

Member
Feb 19, 2023
16
19
devon
I dont think it takes much to to short the battery,mine happened in the cold weather.The set up isnt great with the battery in the frame tunnel. Try other avenues first,i wouldnt like you to go through all the process and it wasnt that.Ive since sold my focus as after seeing the set up lost confidence..
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
I’ve started with taking out the drive unit, which was an easy 10 minute job. Then I took off the all the connectors, gave them a good clean with contactspray and then re-attached them in the hope it would work again, but unfortunately without result.

So, as a next step I need to take out the battery as in order to ‘reset’ it via the button inside the battery. I gave it a try and it seems easy until moment the battery gets ‘stuck’ at some point inside the frame and there is barely no ‘grip’ to take it out.

Does anybody have some tips or hacks for taking out the internal battery?
 

bluesurf989

Member
Feb 19, 2023
16
19
devon
It is tricky as all the wires run down too but it does slot back into place. The difficult part is splitting the case on the battery to access the internals and reset button. I taped mine after. Patience is the key(y)
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
It took indeed some patience, but I managed to get the battery out and split the casing.

The green light on the battery was already on (flickering). I’ve pushed the reset button though (just to be sure) and after that the green light was flickering again, so I suppose the battery is OK…

Then I connected everything back together again, but the issue still remains :(

@bluesurf989 Do you know if in your case the green light was off before the reset? That would indicate that the problem is most likely not my battery.

So, I’m a little bit lost in the dark about the issue now. I think I will start replacing some parts one by one to see if it will fix the issue, starting with the di2 cable from the drive unit to the display, as this is the cheapest part and one I was not able to test without an extra / new cable.

As I had the battery out of the frame when I tested it after the reset, I could see based on the battery indicator lights that the battery was responding to a press on the on/off button, so based on that I think the on/off button is working properly.

So, the story continues… All suggestions / idea’s are welcome.
 

steve_sordy

Wedding Crasher
Nov 5, 2018
9,098
9,589
Lincolnshire, UK
I had an intermittent fault like that on my Jam2. It was traced to a cable that had been trapped and slightly squashed when the battery was replaced. In my case the "intermittent" was traced to a specific movement of the bars that stretched the cable in question. Relatively cheap to fix, considering it was a battery out and in job. The £7 cable took a week to arrive.
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
I had an intermittent fault like that on my Jam2. It was traced to a cable that had been trapped and slightly squashed when the battery was replaced. In my case the "intermittent" was traced to a specific movement of the bars that stretched the cable in question. Relatively cheap to fix, considering it was a battery out and in job. The £7 cable took a week to arrive.
That sounds like a similar case, with possibly the same cause, as the problem occurred after changing my handlebar (and while replacing the handlebar and moving over the cockpit parts and cables one by one, my old handlebar was 'hanging' which possibly could have stretched / moved a certain cable).

Do you still know which cable it was in your case?
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
The only note I have is that it connected the display to the battery. The connection was unmade/made when the cable was stretched or not. I no longer have the bike, since Aug'21.
Thanks a lot! This give me some good hope that it’s indeed the Di2 cable from the display to the Drive unit / Battery, instead of a faulty battery itself.

I’ll order one and test it out - fingers crossed…
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
Today I changed the Di2 cable from the display to the drive unit, but still it won’t charge or turn on.

Something changed now though… Before, the charger flashed green for 30seconds and then keep flashing red.

Right now it is doing the same thing, but after about 30seconds red, it tries to charge again, so the light becomes flashing green again, and then after 30seconds flashing red again, and keeps repeating that loop.

I think I need a new battery, but want to exclude all other factors first.
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
Can you try another charger as they have 'smarts' inside & it could be the charger at fault.
My charger is charging the TEC pack (range extender) properly, and the issue is also that the bike won’t turn on, while the battery is full, so I’m sure the issue is not in the charger.
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
849
544
Derbyshire Dales
I had the same issue with my 2018 Jam 2.
I tried the reset button (strange having a reset button where you have to open a battery, not designed to be opened, to carry out this function) but this had no effect. There was nothing obviously corroded in there but there were hairline cracks around the bolt holes through the battery.
A new battery sorted it for me but strange that your problem started after disconnecting the display. Logic, to me says that it has to be a connection or damage to the display.
Innumerable problems have taught me to accept that Jam2 electronics have a mind of their own and a spiteful one at that.
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
I had the same issue with my 2018 Jam 2.
I tried the reset button (strange having a reset button where you have to open a battery, not designed to be opened, to carry out this function) but this had no effect. There was nothing obviously corroded in there but there were hairline cracks around the bolt holes through the battery.
A new battery sorted it for me but strange that your problem started after disconnecting the display. Logic, to me says that it has to be a connection or damage to the display.
Innumerable problems have taught me to accept that Jam2 electronics have a mind of their own and a spiteful one at that.

Yes, it is strange that the issue started after disconnecting the display. It’s either just coincidence or indeed an the display itself.

But question is then if the battery / drive unit needs to be connected to the display in order charge. If not, it’s most likely the battery…
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
849
544
Derbyshire Dales
The battery on my Focus is currently fully charged (meant to charge it to 60% but forgot it).
If I have chance to get out on the bike and run the battery down a little tomorrow I'll check what happens when the display is disconnected.
Are you using the little plastic tool that came with the bike to connect and disconnect the wires and is there a noticeable 'click' when doing this?
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
The battery on my Focus is currently fully charged (meant to charge it to 60% but forgot it).
If I have chance to get out on the bike and run the battery down a little tomorrow I'll check what happens when the display is disconnected.
Are you using the little plastic tool that came with the bike to connect and disconnect the wires and is there a noticeable 'click' when doing this?
Thanks, that would be great - I appreciate that!

When I connect the cables to the display ports there is indeed the noticable click. On the drive unit side there is no noticable click, but the cable is tightly in place, and as far as I know it never ‘clicked’ on the drive unit side and always worked as it should.
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
849
544
Derbyshire Dales
I had to super glue the display cable at the motor end on my bike as the 'snap' connector was weak, but I seem to remember you had a problem before you ever disconnected the cable at the motor end on your bike. This still might warrant investigation

I will try and update you tomorrow.
 
Last edited:

Peaky Rider

E*POWAH Master
Feb 9, 2019
849
544
Derbyshire Dales
Okay, just back from a ride on the Focus, firstly to check everything worked after a pretty disgusting ride on Saturday and secondly to run the battery down a little.

I have disconnected both cables to the display (in turn) and found that the bike not only turned on in both cases, or at least the on/off switch lit up, it also seemed to take charge in both cases with the green light on the charger flashing as it should.

I thought you could have damaged the mode switch cable as that runs inside the handlebar, but even if you had, my experience has shown that the battery should still have charged and the on/off switch would have illuminated.

The battery on my 2018 Jam 2 gave up the ghost last October so maybe yours has failed after all, as you feared in an earlier post. I think that is more likely than wiring loom problems.

My new battery cost me £510, one where you live should be a bit less.

Sorry I couldn't be more helpful.
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
Thanks a lot for you help! @Peaky Rider.

This will tell me that it’s indeed most likely the battery. The fact that it happened just after disconnecting the display cables and changing the handlebar looks like sheer coincidence.

I will order a new battery and hopefully it solves the problem.
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
849
544
Derbyshire Dales
Thanks a lot for you help! @Peaky Rider.

This will tell me that it’s indeed most likely the battery. The fact that it happened just after disconnecting the display cables and changing the handlebar looks like sheer coincidence.

I will order a new battery and hopefully it solves the problem.
Be interested to hear if that solves the problem.
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
Unfortunately, the story continuous...

As said, the new battery solved the problem. I went for a test ride and all worked fine.

Then, before my next ride, I attached the Focus TEC pack battery extender, but for some reason it was not working (display didn't came on / system didn't turn on), so I took te TEC pack off. Then I tried to turn on the system without the TEC pack but to my surprise the dislpay / system didn't came on again...

-Cables are correctly attached.
-Battery is charging properly (The led on the charger stays green (not blinking red).
-The LED of the on/off switch on starts flashing blue (indicating that the system is out of the stand-by mode), but then on the second press, nothing happens.

I would say it's a broken display unit... which might be just bad luck /coincidence after this recent battery issue, or am I overlooking something?

It starts driving me crazy :(
 

KVDB

New Member
Apr 16, 2023
22
4
Netherlands
Fixed! :)

I realized that after my test ride with the new battery I've torqued up the bolts on the downtube that hold the battery in place (as specified, up to 18nm, with a torque wrench). As there is very limited space between the battery and the frame, I've pinched the cable wire when tightening up the bolts.

I've loosened the bolts, moved the cable wire so that it doesn't 'stuck' between the battery and the frame then tightened the bolts again... BINGO!
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
849
544
Derbyshire Dales
Phew KVBD, luckily that was a simple fix.

Weirdly, after fitting my new battery my TEC battery wouldn't connect either but I don't think it will be the same scenario as yours. I've had the main battery out so many times I could do it in my sleep and I am always careful not to trap any wires. Also, I have a Trailwatts extender and that works fine but I will none the less check to be sure.

I am not too fussed as the TEC battery looks really ugly on the bike and my Focus was so unreliable that I went out and bought a Rail and only use the Focus on shorter rides.

Well done for persevering.
 

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

559K
Messages
28,311
Members
Join Our Community

Latest articles


Top