Where can you find schematics for a 1991 Chevy alternator?

You're unlikely to find a full schematic for a 1991 Chevy alternator readily available online. Alternator schematics aren't typically published as widely accessible documents like, say, a car's entire wiring diagram. The internal workings are considered proprietary information by the manufacturer (Delco Remy was a common supplier for GM at that time).

However, you can find information to help you troubleshoot:

* Repair manuals: A Haynes or Chilton repair manual for your specific 1991 Chevy model (specify the model, e.g., Silverado, Cavalier, etc.) will likely have a wiring diagram showing how the alternator connects to the car's electrical system. This won't be a detailed internal schematic, but it will show the power, sense, and control wires.

* Online forums: Searching on forums dedicated to your specific Chevy model and year (e.g., a Chevy Silverado forum) might turn up discussions where someone has dealt with a similar alternator problem. Someone might have posted a simplified diagram or helpful pictures.

* The alternator itself: Sometimes, a simplified wiring diagram is printed directly onto the alternator casing. Check carefully.

* Parts stores: Auto parts stores like AutoZone, Advance Auto Parts, or NAPA may have wiring diagrams available for alternators they sell. If you provide them with the alternator's part number, they might be able to provide something helpful.

Remember that working with car electrical systems requires caution. Disconnect the battery's negative terminal before working on any electrical component to prevent injury or damage. If you're not comfortable working with car electronics, it's best to take your vehicle to a qualified mechanic.