Update Bosch firmware on 2021 CX motor with Purion

Hi all – it’s been a while.

I have a Whyte e150 RS that I bought new in 2021. It’s never had a service or had it’s firmware updated, so it is still on the original. I understand an LBS needs to update the firmware, which is a bit inconvenient, but anyway…

I took my bike in for a service to have cassette and chain swapped out, and I asked them to update the firmware at the same time. The chap hooked it up to his PC using a USB cable, and the purion display showed ‘USB’. The problem is that his PC didn’t see the connection. We tried a few different cables and even a different USB port on the PC, but no joy.

The chap thought there must be something wrong with the purion display and said he’d contact Bosch to see if they can swap it. Everything works normally, and the port cover on the display looked well sealed and the port itself was clean.

What do you think? Do you reckon there could be something wrong, or do you think there is a different way to update the firmware on a 2021 Bosch motor? The software tool he was using was called ‘DiagnosticTool’ or something like that.

Any ideas? I wish I could do this myself TBH.

I’m wondering if the cable should go to a control box or dongle before being plugged into the PC, or if it should simply be a USB cable connecting the purion display directly to the computer like my LBS was doing?

Oddly my rail was recently updated…was told no new updates since sept 21, had a battery/distance/range update and that’s it, to be honest I’ve no idea if it’s any more accurate.

So I’m saying probably not much to worry about update wise currently.

I think there may have been a 10 ‘something’ power upgrade too.

I had this problem with my Bosch bike. LBS got a new cable from Bosch and it was fine after that.

Any old USB cable won’t do either so no point in them trying various Amazon specials. Needs the Bosch one.

Oh ok.

and this is still not possible to do at home? I’ve been googling for hours trying to find the software utility.

You can probably download the software but without the dongle it’s useless unfortunately.

Dongle’s are only available from Bosch if you’ve completed their dealer training.

So the fact that my lbs literally put a usb cable between my purion and their PC suggests they were missing this single, right?

What is the actual need too this firmware update ? Mine is new 2021 and I’ve not had any updating because tbh It works fine and i dont want any future issue and im a bit afraid updating might do that.

So what exactly is the need ? its not like its connected to anything virtual.

Well there may be 10 newton metres of extra torque available and there are different modes that you might like to try. There are other, less noticeable firmware updates available

So the head unit plugs directly into the computer via a cable and the dongle just looks like a USB drive plugged into a separate port on the computer

There was an update that increased the torque to 75Nm and added a Tour+ mode that automatically changed the output depending on how much effort you were applying. I tried the Tour+ mode but didn’t like it as it wasn’t a smooth transition between the modes. It’s a tick box in the dealer software so a 2 min job to enable/disable. The 75Nm update was good though.

It’s not possible to update at home,  only authorised Bosch dealers can do it.

Bosch should just update using the App

I think that depends on the display / control you have.  I have the smart system with the flow app on my phone.  That means i can update thru the app.  The purion does not have that functionality

@tjagain, apologies you might be right

The update increases the torque from 75 to 85nm

The update increases the torque from 75 to 85nm

Oh yes so it does. My mistake, I sold mine a while ago so forgot the details…

My 2020 E150 came with the torque upgrade, so yours should already have it. A decent shop should make sure any upgrade is done as part of the PDI. Have a check of the software version it’s running. There’s a list of software versions on the Bosch website you can check against.  I wouldn’t  want Tour+ anyway as it will replace the eMTB mode you already have.
TBH I doubt you actually need to update it

I wouldn’t want Tour+ anyway as it will replace the eMTB mode you already have.

I have eco, tour plus, emtb and turbo settings on mine and you can tailor the response in each setting.  I do have the “smart” system tho not purion