why dose my car battary go dead

christinaandisrael
0

Asked by christinaandisrael Mar 16, 2013 at 10:10 AM about the 2005 Cadillac STS 4.6

Question type: Maintenance & Repair

10 Answers

John Sturman
1,655

could be a duff 1 or the alternator could be drawing charge back through a duff zenner diode

3 out of 3 people think this is helpful.
tenspeed
69,445

A diode by definition is a device that allows current to flow in one direction. A Zener diode is a diode which allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage. Zener dfiodes are not used in automotive alternators. --- The battery could be losing voltage due to a parasitic drain. Here's a video explaining it and how to find it. https://www.youtube.com/watch?v=KF1gijj03_0

19 out of 19 people think this is helpful.
tennisshoes
42,865

A lot of things can kill a battery. As I don't have the exact year of the car I'm going to take give you a few things to check. First of all have you battery tested to make sure it is up to the task of holding the parasitic loads this car has. if it checks good then here is a list of what to check next. Glove box light, make sure it turns off, if in doubt remove the lamp, trunk light same thing, underhood light also, interior lights and there is a lot of them, vanity mirror lights, stuck brake lights switch. If all of the lighting check out then you will have to check for excessive draw on the battery, like alternator diodes bad, stuck relays, alarm system. This can get involved. Good Luck

2 out of 2 people think this is helpful.
username
105

One of the most common things I see is one of the lights under the rear view mirror gets turned on when adjusting the mirror and this drains the battery.Check those first. Next disconnect the alternator wiring and check for an excessive drain.....do not confuse the small drain needed for "on star" and other computer related items.Generally a 12 volt test light put between the positive battery post and the positive battery cable with the cable disconnected from the battery should glow dim (normal)but not brightly. remove fuses one at a time until the test light glows dimly. (keep the doors closed and disconnect the under hood light if needed) Dim light OK Bright light DRAIN Disconnect the battery completely for a day or two,reconnect and see if it is still charged. Dead battery.......time for a replacement. Good battery......keep looking for a drain!

6 out of 6 people think this is helpful.
tenspeed
69,445

The Cadillac should have the battery saver function that will shut all circuits down after twenty minutes if a light was left on. It will not shut off the cigarette lighter circuits so don't leave anything plugged in with the engine off.

2 out of 2 people think this is helpful.
tenspeed
69,445

It could be an internal short in the battery. Try disconnecting the negative battery cable at night and see if the battery is flat in the morning.

Js08016
35,145

How often do you drive the car? If it sits for extended periods of time the computers in the car will kill the battery. Disconnect the negative (-) battery cable if you plan on not using the car for more than about a week. HTH. -Jim

5 out of 5 people think this is helpful.
dmarrujo
40

My car will not start. I'm going to see if it's my battery. I use my car once to twice a week. I do leave my cigarette tray open all the time after disconnecting my phone charger.

1 out of 1 people think this is helpful.
dmarrujo
40

Nope..its not my battery..

1 out of 1 people think this is helpful.
pussyy
0

My 07sts Cadillac keeping cutting off when I come to a stop

Your Answer

Add photo

Related Questions

STS
Looking for a Used STS in your area?
CarGurus has 1,361 nationwide STS listings starting at $3,800.
ZIP:

Search Cadillac STS Questions

Cadillac STS Experts

#1 tenspeed
tenspeed
Reputation 240
#2 username
username
Reputation 60
#2 tennisshoes
tennisshoes
Reputation 60
View All

Related Models For Sale

Used Cadillac CTS"
300 Great Deals out of 11,954 listings starting at $1,995
Used Cadillac DTS"
77 Great Deals out of 1,770 listings starting at $3,800
Used Cadillac SRX"
325 Great Deals out of 16,941 listings starting at $3,200
Used Cadillac Seville"
494 listings starting at $2,875
Used Cadillac STS-V"
17 listings starting at $14,894
Used Cadillac CTS-V"
6 Great Deals out of 216 listings starting at $10,888
Used Chrysler 300"
431 Great Deals out of 23,299 listings starting at $2,288
Used Cadillac DeVille"
43 Great Deals out of 2,276 listings starting at $1,195
Used Dodge Charger"
422 Great Deals out of 29,457 listings starting at $3,900
Used Chevrolet Impala"
1,446 Great Deals out of 49,585 listings starting at $995
Used BMW 5 Series"
498 Great Deals out of 16,963 listings starting at $1,950
Used BMW 7 Series"
76 Great Deals out of 4,565 listings starting at $3,990
Used Cadillac Escalade"
153 Great Deals out of 6,881 listings starting at $3,995

Used Cars For Sale

2011 Cadillac STS For Sale
6 Great Deals out of 103 listings starting at $12,900
2010 Cadillac STS For Sale
3 Great Deals out of 51 listings starting at $11,995
2009 Cadillac STS For Sale
6 Great Deals out of 154 listings starting at $8,990
2008 Cadillac STS For Sale
7 Great Deals out of 229 listings starting at $7,950
2007 Cadillac STS For Sale
6 Great Deals out of 218 listings starting at $4,901