JB4 Issues on F30 N55 - DME Codes - N54Tech.com

RileyMK37 · **JB4 Issues on F30 N55 - DME Codes -** 01-12-2021, 11:32 AM

Hi Guys,
New to the forum. Been on bimmerpost for a couple years and the guys there suggested posting my issue here.

I have a used JB4 that I had installed on a 2015 335i, which worked fine. That car was total so I bought another identical one to replace it. I decided to install in preparation for BEF with MHD. I just received a new odb2 cable and the Bluetooth connect device. Installed everything Sunday. Initially I could not get the app to see the JB4, but after a phone reboot and starting the car everything connect fine. Updated firmware to JB4_F_EWG_17_T2, which completed successfully. Afterwards, I started the car again and it sputtered and sounded like it was knocking and the powertrain warnings came then I shut the car down. I tried to reconnect the app and, which would start the connection process and make to “waiting for handshake”, hang for a few seconds and error out.

Tried all suggested troubleshooting, phone restart, checking connections, etc. none worked, and no connection to JB4. Before starting the car again, I disconnect the odb2 cable and it hesitated at first but then idled smoothly, MIL was still on, with performance reduced message. Using MHD app, I was able to pull the DME codes (104401, 119001, 121001, 104B01, and 121521).

With obd2 cable disconnected, I went for drive (with MHD at stage 0) and car was still in limp mode. I then completely disconnected JB4 restoring all factory connections and car is back to normal.

Unfortunately, I still cannot connect to JB4 and I don’t have the usb data cable to see if the until still works.

Hoping someone here has some ideas. Any help is greatly appreciated

Terry @ BMS · 01-12-2021, 12:03 PM

Sounds like a failed firmware update, get an updated 2580 on our site for $25 which will reset it.

RileyMK37 · 01-12-2021, 12:20 PM

Quote:

Originally Posted by Terry @ BMS

Sounds like a failed firmware update, get an updated 2580 on our site for $25 which will reset it.

Thanks Terry!

Is it typical for a failed firmware update to completely successfully on install, work fine on the first connect and engine start, then fail the second time?

Thanks,

Mike

Terry @ BMS · 01-12-2021, 04:44 PM

There is some bug in the app they are working on that will from time to time allow the system to accept a bad update causing the issue. I'm just speculating but sounds like what happened in this case. When you get the 2580 replaced avoid updating firmware again until you get an app update.