MD3/MC42 multi master trouble

Captain Sprocket 1 year ago updated by Gustav Widén (System support) 1 year ago 3

Hi everyone.

I have encountered a strange problem with a MD3/MC42 multi master system and cant't seem to resolve it "quickly".

The problem is that I cannot upload the software onto the system effectively. I have used MD3's and MC42's quite a lot in the past but never together like in this manner and this is the 1st time I encounter this issue (usually I have a MD3 with an expansion module or either a MC42 with a MD4 multi master system with no problems) so this time we wanted to use the MD3 and MC42 together for a project, so I thought it will be basically similar to using a MD4 with a MC42.

I have a 0T id tag on the MD3 and a 1T tag on the MC42, when trying to uplod the software via USB through the MD3 I get the message "incomplete system" and showing only the MD3(Safe mode). But the display also indicated wrong ID tag for some reason.

Then when disconnecting the 0T ID tag from the MD3 and try to upload the software, it works when I click yes after I get this message shown below, both controller get updated though, but then after uploading/startup a message appears on the display stating "CONTROLLER MC42 : NO CONTACT"

Does anyone have an idea what I am doing wrong and where? Am I reading the MD3 manual wrong or something? It states when using it in a single master system no ID tag is required (only a tag on the expansion module if present) but using a multi master system an id tag is required.

I have tested this on 2 different wiring looms also with other new controller modules, all with the same result. 

What am I missing here...?


Satisfaction mark by Captain Sprocket 1 year ago

The MD3 differs from the MD4 in that it does not require an IdTag to be address 0. So in this application, you should skip the IdTag on the MD3. 

The other symptom sounds as if the MC42 fails to read its IdTag on startup, I'd recommend starting by checking that this IdTag is properly fitted. 

As a more general recommendation, I would suggest also preparing the machine for a CAN bus diagnostics interface, so that you are not building something new that relies on the MD3 USB for field servicing later on. I don't think the problem you are facing now is related specifically to the MD3 USB, but over the years, the USB connection on the MD3 has caused loads of trouble. CAN as diagnostics interface is way more reliable. 


Hi Gustav,
Thank you for the feedback... I have found the error of my ways. Nothing Iqan related at all, just something really silly.

It is all good now.