Tapping an OEM CAN Bus [SOLVED]

[P.S.Mangelsdorf]

Over the next few months, I'll like have the opportunity/reason to take CAN logs on a few stock OEM EVs. When I've needed to log in my conversion, I've added a place in the harness to tap the CAN bus, but in these circumstances, I won't have the ability to modify the stock wiring.

What are some good options/approaches to CAN logging with minimal disruption to the harness? Is there a good way to do it that will not damage anything?

[johu]

Apparently there are inductive methods but never tried it. If you have enough time you can find the connector with the CAN wiring (VW orange) and see if you find both sides of it for sale. Then make a tap cable

[P.S.Mangelsdorf]

find the connector with the wiring and see if you find both sides of it for sale. Then make a tap cable

I was thinking about trying this. I know some of the busses are only ever in big connectors though, so not sure how much work it'll be.

I was also thinking about trying to use a needle into each wire of the bus, but not sure if that was crazy.

[johu]

CAN busses are surprisingly picky when tapped that way as in you could disturb the bus. But then you can just remove it.
Perhaps penetrating the back of the connector hits more metal? Works well with unsealed ones at least

[P.S.Mangelsdorf]

Perhaps penetrating the back of the connector hits more metal? Works well with unsealed ones at least

Good point. What have you used to do that? Any specific pin or just a strip of metal?

[johu]

Resistor leads

[arber333]

I used scope needle probes from the back of Nissan chademo CAN connector to scoop up telegrams. And it worked well.

[RetroZero]

I have a couple of Crocodile clips. Tried to get it working, but interference with the bus is all I get.
Parallel scope is by far the least intrusive, just need the right setup. I have a spare Crocodile clip. PM if you're interested....just need to pay postage . Maybe you can find a solution

[uhi22]

pin from the sewing box, they are not very sharp originally, I sharpened them.

[arber333]

I use something like that... https://www.aliexpress.com/item/1005007 ... ry_from%3A

Or that...
https://www.aliexpress.com/item/1005006 ... ry_from%3A

[P.S.Mangelsdorf]

Resistor leads

I've got plenty of those!

[P.S.Mangelsdorf]

pin from the sewing box, they are not very sharp originally, I sharpened them.

I've got a few that are quite sharp and should do the trick

[P.S.Mangelsdorf]

I have a couple of Crocodile clips.

I've use those on my conversion, but had to strip insulation off the wire to get contact.

[RetroZero]

I've use those on my conversion, but had to strip insulation off the wire to get contact.

No need to strip wires.

1730321231125467284868426578146.jpg (34.45 KiB) Viewed 2763 times

[tom91]

No need to strip wires.

1730321231125467284868426578146.jpg

Never got these working reliably for me

[P.S.Mangelsdorf]

Thanks all for the ideas - I'll share if any work particularly better than others. Hoping to do some logging on a friend's Chevy Bolt, and then in a few months the Charger Daytona (STLA Large platform) I just ordered.