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IF A BATTERY IS RUN DOWN AND NEEDS A BOOST, WILL IT CHARGE ...

Sent to Car Experts July 11, 2006 9:17 p.m.

IF A BATTERY IS RUN DOWN AND NEEDS A BOOST, WILL IT CHARGE WHEN THE CAR IS IDLING OR DOES THE ENGINE HAVE TO REV MORE TO CHARGE THE BATTERY?

Optional Information:
2002 Buick CENTURY 3.5?

Customer (name blocked for privacy)

Status: Closed Value: $2

Answer
July 11, 2006 9:32 p.m. (15 minutes and 7 seconds later)

REPLIED

I run down a lot of batteries when in the shop(performing test and such) although its not good for the batteryImages available only to Customers.

However if the battery is good it will charge itself back up during idle and normal driving. If I do run one down I will start the car and let it idle for a while. So to answer the question YES. The alternator senses the state of the battery charge the it will increase voltage to the alternator causing it to charge more on modern vehicles.

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Danny -- Shop foreman -- 99% Positive Feedback on 331 Car Accepts
Senior Master Subaru, G.M.Cert.,Honda cert., Dodge Cert., Ford Cert., 2 ASE Master cert.15 yrs exp.

Reply to Danny
Sent July 11, 2006 9:37 p.m. (4 minutes and 51 seconds later)

DOES THE ALTENATOR PUT OUT MORE VOLTAGE ON HIGHER RPM THAN IDLE.. YOU SAID WHEN THE CAR IS DRIVING. I ASKED IF IT WILL CHARGE THE BATTERY UP IN IDLE..I NEED A SPECIFIC DEFINITIVE ANSWER. I WAS TOLD THAT THE ALTENATOR WILL NOT PUT OUT ENOUGH TO CHARGE A BATTERY IN IDLE. WHAT IS THE ANSWER???

Customer (name blocked for privacy)

Answer
July 11, 2006 9:51 p.m. (13 minutes and 42 seconds later)

REPLIED

The alternator is capable of almost the same output at idle as it is at higher RPM on newer cars. The voltage is controlled by the regulator. The only difference is that a faster spinning(engine reved up) stator can produce slightly higher voltage.

But yes definitively the battery will charge at idle.Images available only to Customers.

__________________
PLEASE -Remember that your Expert will not be paid until you accept an answer and complete the process. Please leave "FEED BACK".

Danny -- Shop foreman -- 99% Positive Feedback on 331 Car Accepts
Senior Master Subaru, G.M.Cert.,Honda cert., Dodge Cert., Ford Cert., 2 ASE Master cert.15 yrs exp.

Reply to Danny
Sent July 11, 2006 9:54 p.m. (3 minutes and 15 seconds later)

YOU KEEP REFERING TO NEWER CARS WHAT ABOUT OLDER CARS. IF THATS THE CASE WHY DOES A BATTERY EVER NEED A CHARGE??

Customer (name blocked for privacy)

Answer
July 11, 2006 10:01 p.m. (6 minutes and 36 seconds later)

ACCEPTED

You have a newer car and the charging system is computer controlled. The computer can up the field on the electromagnetic coils in order to cause the battery to be charged at a higher rate. The older cars could not do this so only raising the speed of the stator in the alt could cause it to charge higher.

The battery has to be charged because especially on newer cars like yours The computers demand a lot of electricity. The battery discharges and the alternator recharges it. The starter also drains the battery as well as the headlamps the alternator keeps this drain in check.

If you have a car that has to have a battery charger hooked up to charge it then there is either

1. A battery drain(such as headlamps left on) or a module bad we call it a parasitic drain

2. A bad battery

3. Insufficient charging (bad alt)

__________________
PLEASE -Remember that your Expert will not be paid until you accept an answer and complete the process. Please leave "FEED BACK".

Danny -- Shop foreman -- 99% Positive Feedback on 331 Car Accepts
Senior Master Subaru, G.M.Cert.,Honda cert., Dodge Cert., Ford Cert., 2 ASE Master cert.15 yrs exp.

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