What a confusing article. Rework and refurbishment are not the same thing.
On subcontracted parts:
Vendor internal inspection does 'in-process' inspection steps and when parts are complete, validates final.
Units that fail inspection at any of these steps go to the Material Review Board, which is manufacturing engineers and QC engineers.
Some dimensions are actually unimportant, but it's not up to inspectors to determine this, it's up to engineers, hence the need for MRB.
Many parts are used 'as is', but ones with important deviations are set aside in a locked room.
It is determined what the root cause is, to correct the process so deviations stop. This is Corrective Action.
They check to see if the CA does what is intended, which is Corrective Action Review.
Many times the initial CA will make a work order to alter the parts already made so they be used, but this is in addition to the process changes to avoid future defects.
The work order to alter parts so they may be used is called rework. The parts were never in a car.
Compliant parts are now shipped to Tesla.
Tesla does receiving inspection, MRB if necessary, and could send parts back to the vendor for rework.
Parts produced internally go through much the same processes, except they must control the organizational tree so that there is no pressure to use defective parts or bypass receiving, inprocess, final, or MRB.
Parts found to be defective at assembly time are very tricky. It's not always obvious what is to blame. It could be a prior assembly, bad tooling, training, process, or the part itself. These are also submitted to MRB.
Refurbishment is what you do with parts that have been USED in a car, were found defective after delivery usually via warranty. After refurbishment and inspection, these parts are used for warranty repairs, or sold as spares.
If Tesla is using refurbished parts in new cars I'd be surprised. I suppose they could, but folk might not want a power steering pump with 100,000 miles on it in their new car, even if it has been refurbished. Everybody uses 'reworked' parts in new planes, trains, and automobiles. These are not used parts. They are parts that required additional work and are every bit as good as a new part if not better.
