Aaah - 120 Ohm termination resistor missing - signals were reflecting straight back into the CAN-Rx line, I guess it thought there was a collision on the bus and did an immediate retry, repeated ad infinitum..

I bought some cheap reflective opto sensors from ebay. The response time of the device itself was terrible, I'm pretty sure it was a fake.

Hi Everyone,
My 1st post, good to finally join you!

I've been using my time in lockdown to bring my e.v. project out of hibernation. The last thing I got working was reverse engineering the BMW Mini Speedometer (Regrets, I've had a few..).
Now I want to send some data to the Speedometer (via the ...