Bosch error code 504.

[Rail7David]

Second time I've had the 504 error code since the software upgrade. The 1st 504 code was cleared and a newer software was installed even though the 85nm upgrade was installed 3 weeks prior. I have made no changes to the motor, such as speedbox, etc. My LBS always wants me to check the speed input and magnet. I thought this was a "tuning" error. Anyone have a similar experience or solution?

 

[IMeasureStuff]

Probably not related, but after I got the first version of the 2021, upgrade to my 2020 motor I had a error 500 after about 6 hours of use. My local trek store sent the details off to Bosch and they recommend the latest version of the motor firmware. Since then everything has been fine.

I guess my point is that to make sure your LBS is sending off the error code to Bosch along with any bike diagnostics.

Good luck

 

[yorkshire89]

Yes this is the motor tamper error code, but there's a few stories on here of people having this who haven't derestricted their motor.
Don't keep riding - I believe the motor goes into limp mode after the third error warning.

 

[Yoak]

It's unacceptable that they don't get on the top of this. We went on a week bike trip (2 hours domestic flight) and one Rail 7 threw a 504 with 3 days left of the trip. We were in a remote place with nowhere to fix it near by. Nothing done to the bike of course

 

[Rail7David]

I had my second 504 error code reset by the LBS. The existing software version was already the newest one. First day riding the Rail 7 I felt the motor cutting out like I had exceeded 20 mph, but I knew I wasn't. I paid strict attention to my mph reading on the Purion controller and realized my speed reading was erratic. The indication was jumping around, at times, by as much as 5 mph. Called my LBS, Folsom bikes, three days ago and am still waiting word for what Trek/Bosch plan to do regarding this warranty issue.

 

[Yoak]

I had my second 504 error code reset by the LBS. The existing software version was already the newest one. First day riding the Rail 7 I felt the motor cutting out like I had exceeded 20 mph, but I knew I wasn't. I paid strict attention to my mph reading on the Purion controller and realized my speed reading was erratic. The indication was jumping around, at times, by as much as 5 mph. Called my LBS, Folsom bikes, three days ago and am still waiting word for what Trek/Bosch plan to do regarding this warranty issue.

This happend to me a lot for a period of time. I had readings from 14km/h to 28 km/h with in a second and you could feel the motor cutting off harshly. I tried a lot of things until a guy at a LBS said that it could be small metal shavings from the disk rotor that interfered with the reader. I took it off and it was small metal shavings stick to the magnet on the disk break. Cleaned it off and it worked properly ever after

 

[Stanpipe]

^^^^^ what YOAK said. Happened to me and cleaned off sensor on disk. Now works fine.

 

[Rail7David]

I have received multiple suggestions that my two 504 error codes and the erratic mph readings are caused by metal pieces on my speed sensor magnet. I wish this was true, but is not the case. I have cleaned the magnet and the LBS replaced the magnet and the problems persisted. My bike is presently at the LBS having the speed sensor pickup replaced. Will post whether or not this solves my problem.

 

[damdegraff]

Any luck getting your sensor fixed?

 

[Rail7David]

The sensor was replaced and has seem to have solved the problem. However, it's winter where I live and all the trails are snow covered and I have switched to skiing, so I haven't put many miles on the bike lately.

 

[JohnH]

I know how I triggered it on a Powerfly FS4... I was using walk mode on a steep hill and accidentally hit the gear shift and changed 2 cogs. Immediate Error 504. It has taken 2 days to get someone to reset it with a software update. And, there were a lot of filings on the speed sensor too.

 

[folmonty]

New here but have lots of experience with vehicle sensors. Whenever a WSS (wheel speed senor) is used they're so susceptible to any minor variations. Since this Bosch motor is taking it's reading from one of these it's probably good practice to keep a close eye on it. Noticed even taking the wheel off, it's right there where it could be hit or while the wheel is off just clean it as preventative maintenance. Looks like Trek uses a nice mounting system which is protected pretty well but it's still nothing more than a magnet.

 

[bodgy]

Hiya,

Just wanted to chip in to the thread.

I’ve had the 504 (inevitably at the furthest point of a big family-day-out route ?). The shop that I bought from didn’t have authorised service dealer status & software (dammit) so had to go to a not-so-local LBS. They plugged it in and advised that in the absence of tampering the 504 also indicates that it could be a wheel speed sensor alignment / calibration issue that would need to be fixed by an authorised dealer (Focus dealer, in my case).

Bloody annoying and increasingly expensive in time, fuel, labour costs and missed biking opportunities.


Will check the sensor for swarf and metal dust as well, thanks for the tip. ?

 

[folmonty]

Really think Bosch and related brand name dealers need to make diagnostic software available to the public for those of us who like to work on their own equipment. Not like most of us don't know how to do these things. Finding that many bike shops really don't have the knowledge required to be working on eMTB's or any ebike for that matter. It's just something that's developed so they're taking advantage of it. That's fine also as they'll learn over time but many bike shops don't tend to keep staff for long which requires a different level of training for the new ones.