HowStuffWorks: How Turn Signals Work
Photographs and animations describe the unusual device called a thermal flasher that makes your signals flash, and shows how turn signals cancel themselves after you've made your turn.

OBD-II - On-Board Diagnostic System
Dedicated to helping the home and independent technician understand and use OBD-II technology through text, photos, and a discussion forum.

Understanding Alternators: an Overview
Features diagrams and technical information applicable to all automotive alternator systems.

Car Battery FAQ
Battery maintenance, myths, electrical testing, jump starting, failure and replacement are all discussed.

Automotive Online Electrical Tutorial
Covers basic electrical issues, alternators, relays and circuitry.

Jumpstartcar.com
Information and products to help jump start a car and become a roadside emergency expert.

Volvo Electrical Systems
Contains theory, troubleshooting and maintenance.