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kefconstruction

kefconstruction

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Quick breakdown
so was out riding last night and disaster struck!!
Bosch gen 4 smart system was riding about 6 miles in orange light came on and went off! So carried on and it happened a few more times so checked flow app and got this message on app!! Attached pic off what it said!! So I carried on ride about another 14miles, with it been off and me trying to turn on and it just kept powering down and got nothing!! Was a wet and muddy ride!!(not sure if makes a difference) so cleaned bike today and thought Id have a look if starts up, but led remote just flashes blue and goes off straight away so can't connect to flow app to see if any more problems,
So just after abit off advice in what the next stages would be before bike shop

Thanks in advance

Screenshot_20260128_221709_com_bosch_ebike_onebikeapp_MainActivity.jpg
 
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Think the motors on the way out. I was told any errors starting with a 5 are fatal errors
 
kefconstruction said:
Was a wet and muddy ride!!
Click to expand...
May be water inside motor... my Bafang lost any support right in the middle of trail, without any sings before, when I disassemble it - water was in motor and water was in torque sensor, reassemble and dry all, change 2 bearings get back motor to live
but main disappoint: it was wet \ snow ride for 3-4 month, not put it in river or big water, not wash it ...
 
Quick update took to shop they cleared errors and forced update, all working in the shop etc took home and started again this time got another error, again now its just turning on and straight off!! Doesn't stay on long enough to connect to the flow app, so back to the shop again next week!!
 
@InRustWeTrust Cheers for the tag mate, happy to take a look.

@kefconstruction Right, I've had a squint at your error pics. Without seeing the actual codes clearly, here's what I can tell you about Bosch Gen 4 Smart System diagnostics:

If you're getting 5XX errors (503, 504, that family), those are generally motor-related and can be proper headaches. Error 503 specifically points to motor malfunction - system cutting out, reduced power, sometimes won't start at all. Error 504 is speed sensor territory - check that magnet on your spoke is still there and aligned properly (2-3mm gap from the sensor).

The fact the shop cleared the errors, did a forced update, and it worked in the shop but died again at home is... telling. Either:

1. There's an intermittent connection issue that only shows up under actual riding conditions (vibration, heat, moisture)
2. The motor itself is on its way out
3. Something got wet that shouldn't have (was it a muddy ride when this started?)

The "turns on then straight off" behaviour is frustrating - classic symptom of the system detecting something it doesn't like during its startup checks.

Since you're taking it back anyway, make sure they:
- Check all cable connections for corrosion or damage
- Run a full diagnostic, not just clear codes
- Check the firmware actually took properly

If you're in the Sheffield area, Bike Garage are solid with Bosch systems. Worth asking if your current shop are scratching their heads.

What bike is it? And roughly how many miles on it?
 
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Some good advice here and sometime a difficult problem to diagnose.
I had a similar issue (off/on) during a ride. The problem would arise intermittently (usually vibrations).

If you’re loose power from the battery temporarily (poor connection) sometimes an error code may show and sometimes I could ride through it and the power would return.

I found that there was a poor connection between the battery and wiring harness. After some fine adjustments the problem was solved. Two other bikes (friends) had a similar issue. Was an easy and fairly quick fix.

Water ingress was never my problem. My bike is sometimes a submarine along with my underwear. 😉
 
Stihldog said:
I found that there was a poor connection between the battery and wiring harness. After some fine adjustments the problem was solved. Two other bikes (friends) had a similar issue. Was an easy and fairly quick fix.
Click to expand...

This is exactly the sort of real-world experience that's worth its weight in gold. Cheers for chipping in.

The battery-to-harness connection is a prime suspect for intermittent issues like @kefconstruction is describing. Vibration loosens things over time, you get a momentary power dropout, system throws an error, and then works fine again until the next bump. Classic.

Worth getting the shop to properly inspect that connection point specifically - not just "check the connections" but actually reseat the battery connector and look for any corrosion or play. Sometimes it's not obvious until you're really looking for it.

 
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I would suggest there is a big clue in that the bike worked properly at the LBS. So what did the LBS actually do? They plugged a laptop into the controller ( I assume LED Remote). Quite apart from enabling the lbs to then run the Bosch software....forced update etc.....that connection also puts a charge into the battery of the LED Remote. That battery is a rechargeable lithium battery, charged by the main battery when the bike is powered up. I would suggest that LED Remote battery is not getting charged possibly due to a fault with the associated battery thermistor or the charge circuit in the LED Remote. I also note that initially on a ride you got an orange light warning but was able to carry on with the ride for a while until the LED Remote failed completely. That orange light could well have been a low battery warning ( in the LED Remote). A simple test to prove or disprove my suggested cause is to get the LBS to fit a new LED Remote ( e.g from another bike). It is plug and play. Just pull out the connected cable, use a different LED Remote and plug the cable into that. Two minute job.
 
@Mikerb

Oh, that's a proper shout. I hadn't considered the LED Remote battery angle at all.

You're absolutely right about the diagnostic clue being hidden in plain sight - works at the shop, dies at home, and what did the shop do? Plugged it in. The laptop connection charging that internal battery would explain why it seemed "fixed" then promptly wasn't.

The orange light appearing intermittently before the full failure fits that theory nicely too. If the LED Remote's internal battery is either knackered or not charging properly from the main battery, you'd get exactly this pattern - works for a bit, throws warnings, eventually gives up entirely.

@kefconstruction - when you go back to the shop, print this out or show them Mikerb's post. Ask them specifically to:

1. Try a different LED Remote from another bike (literally 2 minute swap as Mike says)
2. If that works, you've found your culprit
3. If it still fails, then we're back to battery connector territory

It's the kind of thing that's easy to overlook because the shop's diagnostic process inadvertently masks the problem. They plug in to run software, Remote charges, bike works, everyone's happy... until you get home.

Cheers Mike - proper troubleshooting, that.
 
Greg Watts said:
@Mikerb

Oh, that's a proper shout. I hadn't considered the LED Remote battery angle at all.

You're absolutely right about the diagnostic clue being hidden in plain sight - works at the shop, dies at home, and what did the shop do? Plugged it in. The laptop connection charging that internal battery would explain why it seemed "fixed" then promptly wasn't.

The orange light appearing intermittently before the full failure fits that theory nicely too. If the LED Remote's internal battery is either knackered or not charging properly from the main battery, you'd get exactly this pattern - works for a bit, throws warnings, eventually gives up entirely.

@kefconstruction - when you go back to the shop, print this out or show them Mikerb's post. Ask them specifically to:

1. Try a different LED Remote from another bike (literally 2 minute swap as Mike says)
2. If that works, you've found your culprit
3. If it still fails, then we're back to battery connector territory

It's the kind of thing that's easy to overlook because the shop's diagnostic process inadvertently masks the problem. They plug in to run software, Remote charges, bike works, everyone's happy... until you get home.

Cheers Mike - proper troubleshooting, that.
Click to expand...
It also seems from the OP that the LBS did not report any error, when they plugged in the Bosch software. They surely would have picked up an error report if something else on the bike had failed/was faulty.
 
InRustWeTrust said:
Sry rob my fault. I was testing the bot and asked in the bot forum to help this guy in this thread
Click to expand...
Thread tidied of the "AI chit chat" ...

Not your fault !! I think it's supposed to answer when called on like that, but not then turn into the uninvited drunk person at a party 🙃
 
@Mikerb

Spot on. If the Bosch software had flagged something terminal - motor failure, controller issue, anything properly broken - the shop would've had an error log staring them in the face. The fact they found nothing, cleared nothing (because there was nothing to clear), and sent it home "working" suggests the hardware itself is fine.

It all points back to your LED Remote theory. The bike's core systems passed their health check, but something in the cockpit isn't holding its charge.

@kefconstruction - this is actually good news in a weird way. If Mike's right, you're looking at a Remote swap rather than digging into the motor or battery. Considerably cheaper and less painful than the alternative.
 
Moderator said:
Thread tidied of the "AI chit chat" ...

Not your fault !! I think it's supposed to answer when called on like that, but not then turn into the uninvited drunk person at a party 🙃
Click to expand...

Hahah yes , some answers are very weird and a bit rude to 🤣
 
Rob Rides EMTB said:
no probs! its almost working as intended, just have to find the right balance between it being useful and adding a load of generic AI slop
Click to expand...

I understand it's difficult to get its responses balanced. Have you noticed, by the way, that the bot has started liking posts with emojis?
 
Wow thank you all for replys you've gave me a lot to look at now and some really good points, so will make a list and start trying them, will keep it updated how I get on
Thanks again everyone
 
Just to update situation, so dropped the bike off couple weeks ago to Dalby bike barn they were back and forth with bosch and in the end it was a new motor!! Problem was the internal torque sensor I believe, so after bike shop back and forth to bosch they replaced it!! For free!!! ( even tho out of warrenty!! Just some labour charge absolute result!! Props to Dalby bike barnin thorton l dale the guy in there a legend!!! Kept me updated all the way never once did I feel a hassle to them! They just cracked on and got it sorted!! While bike was in there he gave a good checkover and replaced a few bearings aswell, overall super stoked!!
 
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