[Tangurena2]

The car companies won't let that information out to independent repair shops (except where mandated by laws). The "right to repair" movement is one attempt to make it possible.

The worst offender is John Deere and their newer farm tractors. Only authorized repair centers can get the software needed to troubleshoot the vehicles. Part of why Deere does not want details out there is that some tractor models have the exact same engine, but different power outputs based on how much the customer paid. One could "unlock" a more powerful engine without paying corporate. The really big "implements of husbandry" (as my state calls them) can cost $500k. At peak planting/harvesting time, you can wait weeks for a technician to come to your farm. Or spend a few thousand dollars having it driven to the dealership by truck.

[bdavbdav]

IMHO, the decent indies are all sat on copies of either the original dealer software (by whatever means…) or copies built by companies to emulate original dealer software (VCDS for VAG for example)