On Sat, 8 May 2021 15:45:02 +0000, Keithv
wrote:

toyota land cruiser for one, it had a weird 24v starting system with a parralleling relay so the 2 x 12v batteries could be charged from 12v alternator
No they didn't. They had full 24 volt systems including the
alternator on all diesel Cruisers. At least all the ones sold in
Canada before 2000. To operate 12 volt accessories required a buck
converter. I used to produce and provide a system to adapt them to tow
12 volt trailers. I was also a Toyota service manager back then.