
Originally Posted by
pingu
The CAN bus is a serial bus (a bit like RS232 but electrically a bit more electrically rugged so it doesn't get upset by all the other electrical stuff - like alternators and spark coils - going on under the bonnet).
If you're getting a CAN error then it might simply be a case of a defective wire to whatever module (auto controller?) the DME is attempting to communicate with. Can you check out the wiring? If I remember correctly, the CAN bus is a differential bus (i.e. two wires; it's not a case of one being Tx and one Rx, they're both used together - but only one module (e.g. the DME) can talk at a time).
The CAN bus was specifically designed to be used in an automotive environment so I'd be surprised if hot plugging your DME had killed the CAN bus interface.