Automotive Elrectrical Tesring is related to car battery installation. The reasoms behind car batery installation vary. Most car batteies last 3 year or more. When the car battery goes dead you must load test the batttery at a local auto parts store. Usually they will charge the battey and load test it for you. If the baatery is found to be good the next step further testing is needed. Alternator and starter testng are the next steps recommended. Both components can usually be tested while still installed in the vehicle. Consult a vehicle service manual for your speciic vehiicle to determine the exaact steps First check the cables on the battery they must be clean and tight.Check the battery electrolyte/ if it is low charge the battery.The next step is to examine the wires on the alternator. iit mui=st be clean and tight. Also examine the drivebelt and the alternator mounting bolts. stasrt the engine and listen for abnormal noises coming from the alternator. using a vpltmeter with the engine off check for battey voltage.It should be about 12 volts. Start the engine of the vehicle and check the voltage of the battery it should be aproxomatily 14 to 15 volts. Most alternaors have a test holeon the rear of the part. Ground the tab by inseertung screwdriver bladeinto the hole and touch the tabs and case at the same timeYour voltmeter should read 15 volts or higher with the tab and test hole grounded. if the voltmetr shopws low battery voltage the alternatore is faulty and musat be replaced. if the votage reading bis higher than 15 nd a no charge condiotion is present the regulator or field circut is thge problem. Most alternators have the regulator built inside of the alternator caing itself.. Some cars use an external mounted regulator in either case the alternator must be replaced .