How to test to see if you have a bad battery or bad alternator

Asked by Jun 29, 2015 at 11:11 PM about the 1997 Ford Crown Victoria 4 Dr LX Sedan

Question type: General

I started the car disconnected the battery
the car shut off within 20 seconds I believe
its the alternator I've taken the battery down
to the local auto parts store and they tested
it and they said It was good and within
range. But the battery was to low to run test
On the alternator so I have the battery On a
charger

2 Answers

88,785

First of all never ever disconnect a battery cable with the engine running, you can cause a voltage surge that can fry electronics. I had a customer that did that to his crown Vic and it wound up costing him 1500 bucks to get it running again. The proper way is to have a shop check the system on these high output charging systems, most of them are now computer controlled, so even thought the alternator checks good out of the vehicle it still may not work when in the car. You can check the battery the old school way by making sure it is fully charged, then just turn on the headlights with out the engine running for 20 minutes, if will crank over the engine the battery is strong enough to run your vehicle, if it don't crank it replace the battery. Or your local parts store can run a load test on it to see if it can handle full load or not. HTH

1 out of 1 people think this is helpful.

Thank u will try that . I'm charging the batter now

Your Answer

Add photo

Related Questions

Search Ford Crown Victoria Questions

Ford Crown Victoria Experts

#1 Tracy Hooks
Tracy Hooks
Reputation 1,710
#2 Tom Demyan
Tom Demyan
Reputation 890
#3 FordNut
FordNut
Reputation 860
View All

Related Models For Sale

Used Mercury Grand Marquis
21 Great Deals out of 1,810 listings starting at $500
Used Lincoln Town Car
31 Great Deals out of 1,818 listings starting at $1,650
Used Chevrolet Impala
589 Great Deals out of 29,008 listings starting at $1,300
Used Ford Mustang
326 Great Deals out of 45,933 listings starting at $2,000
Used Ford Taurus
203 Great Deals out of 19,353 listings starting at $500
Used Ford F-150
2,431 Great Deals out of 211,451 listings starting at $895
Used Ford Explorer
760 Great Deals out of 75,119 listings starting at $750
Used Chevrolet Tahoe
630 Great Deals out of 27,855 listings starting at $600
Used Chevrolet Caprice
145 listings starting at $11,995
Used Honda Accord
718 Great Deals out of 83,067 listings starting at $500
Used Chevrolet Camaro
137 Great Deals out of 35,611 listings starting at $1,995

Used Cars For Sale

2011 Ford Crown Victoria For Sale
3 Great Deals out of 125 listings starting at $5,450
2008 Ford Crown Victoria For Sale
114 listings starting at $2,990
2007 Ford Crown Victoria For Sale
77 listings starting at $3,995