This isn't true for many makes and models. It's different than older models because troubleshooting or servicing starts with interrogating or commanding the car with specific software that isn't basic OBDII but with OBD adapters and cheap software both my 2010's Volkswagen and Jeeps can be diagnosed and serviced with an OBD reader.
Ironically my old Toyota is one of the hardest to really get at sensor and dealer-software changes.
In personal experience, VW manuals are atrocious to figure out while Toyota, at least around 2000 put out wonderful service manuals even if the ECU's are locked down.
Ironically my old Toyota is one of the hardest to really get at sensor and dealer-software changes.
In personal experience, VW manuals are atrocious to figure out while Toyota, at least around 2000 put out wonderful service manuals even if the ECU's are locked down.