Focus jam 2 complete wiring loom

R120

Moderator
Subscriber
Apr 13, 2018
7,819
9,190
Surrey
All Shimano bikes switch themselves off after a certain period of inactivity. On my Vitus I think its about 10 or 15 minutes.
 

Danijel

Member
Aug 13, 2018
54
52
Netherlands
Very interesting to see the wiring loom like that Russ. Thanks for sharing. I was wondering if any of you guys experience the blue power light randomly glowing when lifting or turning the bike? The light also lights up when washing the bike. Strange behaviour if you ask me.
 

bissona

Active member
Patreon
Oct 14, 2018
137
106
Guernsey
I was wondering if any of you guys experience the blue power light randomly glowing when lifting or turning the bike? The light also lights up when washing the bike. Strange behaviour if you ask me.

Yes, all of those things happen with the three we have over here. The blue light glows brightest when wheeling the bike backward!
 

Akiwi

🐸 Kermit Elite 🐸
Feb 6, 2019
986
1,292
Olching, Germany
Very interesting to see the wiring loom like that Russ. Thanks for sharing. I was wondering if any of you guys experience the blue power light randomly glowing when lifting or turning the bike? The light also lights up when washing the bike. Strange behaviour if you ask me.
I had a similar behaviour. I had the problem that I would turn the bike off, and the light would turn on and off every few seconds and just continue doing it.
That was after another problem I had where I could occasionally not turn my bike on if I turned it off. And then when I shook the bike, the light would glow for a while.
I have a video of it doing that.

Not sure if this link works. Sorry it is in German, I made it to send to Focus.
https://photos.app.goo.gl/RaFq4RdaKiLTwJfZ9
 

Apr 29, 2019
17
3
Boulder
Hi all - clearly, I've found the experts..... I have an extra internal battery (long story...) and wanted to consider using it as an extender on long rides. Yes, I have the T.E.C. pack, but still, 700ish watts won't keep up on a full day of exploration with my buddies and their 1000W Levo's. Ideally, I'd like to wire a RoPD connector to the old internal pack an use it as a new T.E.C. pack. Anyone have any experience with this? Although the outside label diagram on the battery shows 4 points of connection, once you remove the black sealed silicone piece I see there are at least 8 wires in that hornet's nest. Looks like from the above pics only the grey and white wires are utilized. Think it's worth it?
 
Apr 29, 2019
17
3
Boulder
Yes, the extra battery holds a charge. It was the original OEM and had about 20% less holding capacity out of the box and thus replaced by the dealer. Now I have this battery and desperately want to use it as a range extender!
 

Gspot

Active member
Jul 28, 2019
135
22
NW
I need to charge the battery externally. Anyone charge the battery out of the bike?
 

merlot

Member
Apr 27, 2021
25
7
ES
Hello,

Does anyone have a schematic of the Jam2 Shimano cables?

In the first pictures I recognize the swhitch and the charging port, but I don't know where the other connectors are pluged (motor controller, battery, display, ...). Tis would help if we have to solve some issue.

Thank you
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
847
538
Derbyshire Dales
My 2018 Jam2 has finally, after many many hiccups, totally given up the ghost and is now as dead as a dodo.
I have removed the motor and battery to clean all connections and have substituted the display screen and mode selector switch with those from another Shimano bike to check their possible failure. All to no avail so it looks like the wiring loom or the battery is/are to blame.

The bike is well out of warranty, although the warranty on its replacement motor has only just lapsed, so I am looking at sorting it myself but do I start with a new loom or a new battery?

Also, does the TEC pack battery have its own BMS system meaning the bike should still work once that unit is plugged in?

My Focus has been very temperamental when switching on for the last couple of years, whereas the "cheap" Canyon Spectral On, with the external battery, which I bought as cover for my unreliable Focus has never missed a beat, which supports theories forwarded earlier in this thread about avoiding cobbled together systems.

Final question, could an aftermarket range extender cause issues with the BMS?
 

L1482

Member
Aug 9, 2020
24
4
Sunderland
I may as well reply in here, although my issue is different...

So my 2019 Jam2 9.7 has always been awkward to fire up, when running the T.E.C. battery. But lately it is often turning itself off. It doesn't seem to be related to vibration etc as it can do it when not even moving. But arguably, it happens more so on trails.
I have 3 T.E.C. Packs and 3 cables. All have been contact cleaned and sometimes it seems sorted.

It's so intermittent that it has me suspecting the wiring loom or internal battery - even though it fires up straight away and run until drained each time, every time on the internal.

I'm going to strip it this week and test through the loom etc.

As those afflicted know, this is infuriating. With a ZEB and Super Deluxe fitted, it transformed what was already a cracking bike.
I hope it has life left in it, yet!
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
847
538
Derbyshire Dales
I've just spent £530 on a new battery and, for now, the bike turns on as it should. However, when I connect the TEC pack the bike turns itself off.
Beginning to think I wasted £530 as the range given by the internal battery alone is not sufficient for my needs.
 

L1482

Member
Aug 9, 2020
24
4
Sunderland
I've just spent £530 on a new battery and, for now, the bike turns on as it should. However, when I connect the TEC pack the bike turns itself off.
Beginning to think I wasted £530 as the range given by the internal battery alone is not sufficient for my needs.
That's shit, mate! Dunno why these things are so temperamental.

A new battery is something I may be looking at. I don't understand how the BMS etc works. Hopefully when I pull it apart I will gain a little knowledge on the subject.

Can you think why my internal would appear fine, yet the bike keeps switching off in use, when various TECs and leads are fitted?
 

Peaky Rider

E*POWAH Master
Feb 9, 2019
847
538
Derbyshire Dales
"Can you think why my internal would appear fine, yet the bike keeps switching off in use, when various TECs and leads are fitted?"

No, I'am at a loss.
Yours problem seems to have developed with your existing battery, where as my only occurred when a new battery was fitted, yet we both have a similar problem linked to the extender.
I could take it to a dealer to see what a diagnostic might throw up but the first thing they would do is update the software, which i would not want, for obvious reasons.
 

gmed

New Member
Nov 6, 2023
2
1
United Kingdom
Removed the complete wiring harness from the jam last night to check for continuity of the various wires , I had to satisfy myself that no fault existed with the loom it's self, all check out ok.
However, all the wiring that comes out of the battery about 3" latter disappears into a black rubbery lump of silicone like material.
I picked all this apart, my biggest surprise here was nothing is soldered together, only crimped.
The thin wiring joints had heat shrink insulation , very good, but the heavy black and red cables ( the main current carrying cables !)
have no insulation!! Only separated by the silicon like material. Fair enough the are not touching , l would soon be aware of it if they did!!,
It's hardly a well executed design?
I'm just pedantic when it comes to doing things properly .
Henry Royce (one half of Rolls Royce) once said "whatever is rightly done, however humble, is noble"

Russ. View attachment 10954 View attachment 10955 View attachment 10956
Any idea what the black cable in the third picture does ?
 

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