P1854: Drive Hardware Fault - Data Bus Error 18262

"I recently received this error message from the engine control unit (ECU) of my 1998 Volkswagen Golf IV 1.9 TDI."
Can someone tell me what that's all about?
The engine itself functions normally.

Given the year of manufacture, the CAN bus should actually be irrelevant, as everything is still connected in a conventional way. Does your ABS system use a CAN bus? I could imagine that the ABS might be connected to the engine control unit (ECU) via CAN, but I don't really think so.

The instrument cluster is certainly not connected to the engine control unit (ECU) via CAN. The latter can already support CAN, because it was designed for future model years. I would actually say, if it does everything... it's good .