I bought it yet I don't know what it is?

Why is it so hard to find useful info about newer cars? I want to know my alternator?s specifications, specifically maximum amperage, as well as many other specifications, maybe a wiring diagram. I guess I'm looking for a detailed description of what I bought, with the receipt. Must I buy the dealer shop manuals at $150 apiece

If you own the car, and you plan on keeping it and maintaining it yourself, $150 for a shop manual is a smart investment that will pay for itself. You could get a subscription to alldata, if you want…

Check out ebay for possible manual or a download site for them.

If you would have posted your make,model,year perhaps someone could have provided you with the info you need but noooooo…

Call a dealer with the the vin # handy and ask them to look up what amp the alternator is. Depending on the make you need either the entire 17 digits or the last 9 if it’s a Chrysler or the last 8 for most makes. They can get into the manufactures web site and look at the vehicle build sheet.

GM used to stamp the housing in 1/4" numbers on one of the flange ears. 37A, or 70A or whatever eh.

Thanks for the replies! I called the Toyota Marin dealer with the VIN to my 2006 RAV4 V6, the alternator is 100 Apms. I installed a second (smaller) battery, for the custom stereo system, with a battery isolator, earlier, in a 1986 Camery. These parts are now in the garage fishing for time and money. The shop manual for that beauty was complete at $100.
I recently installed a toe hitch and harness with the help of Joe, an awesome technician at the dealer, who, after asking, gladly printed the relevant sheets from the shop publications computer. How do I politely ask for the relevant sheets describing the wiring harness? Or, better yet, is there such a thing as a library or copy shop for technical papers such as these; where one could pay the appropriate fees to receive copies of manuals or code books?

Did the Dealer say what part of the VIN led them to conclude your alternator was 100 amps (perhaps it is the only choice so knowing the VIN only appeared to be required). GM lists these options on a RPO tag with limited info from the VIN.

Keep in mind that even though your alternator is rated at 100a a 15% to 20% reduction in rated output is normal and the alternator will still pass a output test even though it cant put out 100a.