The purpose of the battery is to supply the necessary current to the starter motor and the ignition system while cranking to start the engine. It also supplies additional current when the demand is higher than the alternator can supply, and acts as an electrical reservoir.
The automotive battery, sometimes known as a lead-acid storage battery, is an electrochemical device that produces voltage and delivers current to start the vehicle. When the automobile is running the battery, electrochemical action is reversed, recharging the battery and allowing it to have many years of service.
By having regular battery and starting / charging system checks (about every six months), you can identify many potential problems before a failure occurs. During this test, your technician should check battery condition, connections and alternator output. It is also important to regularly inspect the condition of the alternator drive belt and replace if necessary. An alternator drive belt that is slipping can damage the battery.
Without a properly functioning battery and charging system, your vehicle’s performance will be affected. Most modern vehicles are outfitted with computer controlled fuel delivery, ignition systems, transmissions, sensors and microprocessors that require a steady supply of controlled electricity to function properly.
What is a starter motor?
The starter motor is a powerful electric motor, with a small gear (pinion) attached to the end. When activated, the gear meshes with a larger gear (ring), which is attached to the engine. When the engine starts to spin faster than the starter, the starter automatically disengages.
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What else is affected?
If the battery in your car is in poor condition or nearing the end of its life, the alternator may not supply the required amount of alternating current (AC) to keep the vehicle operating properly. If any other components in the charging system are malfunctioning, the entire system will suffer from poor performance or system failure.
Batteries almost never fail if they’re in good condition. To prolong battery life, the battery, terminals and cable ends should be kept clean and free of corrosion. The battery and starting/charging system should be periodically tested for proper performance. Many testers utilized today are able to predict when a battery is near the end of its useful life.
Things to watch for:
• Make sure the battery rating meets at least the minimum cranking amperage (CA or CCA) requirement for your vehicle
• Even today’s maintenance-free batteries need periodic inspection & cleaning to ensure proper operation
• The fan/alternator or serpentine belt on your vehicle is an integral part of the charging system
• Belts should be inspected for signs of wear and proper adjustment
• Loose or corroded cable ends may prevent your battery from maintaining a full state of charge
• Heat causes more damage to batteries than cold weather, but starting a vehicle in cold winter weather puts more strain on it
Faulty Batteries Can:
• Cause headlights, dashboard lights & interior lights to go dim when starting the car
• Prevent the car from starting
• Cause lights to be dim when the car is off
Faulty Battery Connection(s) Can:
• Prevent a car from starting just like a bad battery
• Result in loose or corroded battery cables and terminals
Defective Relay/Solenoid(s) Can:
• Cause poor starter performance while lights still work fine
• Cause intermittent starting
• Result in a failure to start
A Malfunctioning Starter Can:
• Cause a clicking sound when you turn the key
• Result in a failure to start
• Cause starting to be slow or labored
• Cause lights to become dim when attempting to start the car
Cracked or Frayed Fan Belt(s) Can:
• Cause a squealing sound
• Cause a discharged battery
• Result in noisy operation if too tight
• Prevent alternator from charging if the belt is broken
A Faulty Alternator Can Cause:
• Insufficient battery charging
• Poor accessory & light operation
• Erratic engine operation
• Illumination of dash warning lights