Can I Piggyback On To An Existing Car Can Bus Network

Hi All,

I want to control a couple of slave Arduinos from a master Arduino using can bus. Can I piggyback on to the cars existing can bus network as long as I use the correct baud rate?

I don't particularly want to run new looms so if I can, use the existing loom.

Cheers,
Mike.

s200bym:
Hi All,

I want to control a couple of slave Arduinos from a master Arduino using can bus. Can I piggyback on to the cars existing can bus network as long as I use the correct baud rate?

I don't particularly want to run new looms so if I can, use the existing loom.

Cheers,
Mike.

Yes, so long as the CAN bus load remains resonable when you add your arduinos on the network, otherwise you'll start running into problems as well.

How many arduinos u planning to add to the network? Adding too many may impact the bus impedance. I would suggest u check the CAN bus waveform before and after adding all your arduinos to make sure it is not distorted.

Also you need to make sure that the CAN IDs you are going to use will not interfere with the car systems.

If you are sure of that and maintain the bus load, it should not be a problem

Thanks for your reply.

I will be doing testing first with a sniffer and oscilloscope to check ids and waveforms etc.

It will be 3 Arduinos, 1 master and 2 slaves.

I have the cars service manual with diagrams and impedance levels so I have somewhere to start :slight_smile:

Mike.