You won't find a person in an automotve OEM to talk to you about this, and nor should you try, for all the reasons given in iLuvLogix reply. But perhaps this is your interpretation of the task, rather than the actual task set.
If this is a serious company, I suspect the task isn't to get on the phone to the purchasing director at BMW and try to represent (/accidentally mis-represent) their company and sell them a product about which you know almost nothing, but to identify which OEM(s) might be interested, and which of their policies/plans the "software based vehicle solution" aligns with that you could - in theory - use to show benefit to the OEM of working with/buying the company's solution.
For some trivial examples, there's little point talking to Tesla about engines or BMW about vans, but if it's to do with hydrogen power, Toyota is the first OEM you should look at.
TL;DR: I think they are asking you to demonstrate that you understand the potential marketplace and can do the research that would be needed before approaching a company to pitch the product, not actually make a sale. Whether the work involved in that is reasonable for you to put in at this stage of the recruitment process is your call.