My Car Won't Start, I NEED HELP!

[Edith De Jesus]

My car won't start,

I Checked The Battery And Replaced The Alternator

It only stars when i jump start it and then the battery discharges with in an Hour Or two!

I don't know what it could be anymore , any help?

[Cadillac Jim]

Discharging a battery from a full charge in an hour or two means that the headlights are on or some similar drain. Check the smart-stick on the left side of the steering wheel and see if the headlights are on Manual On. They should be on Auto. The word Manual/Auto will appear on the message center near the speedometer when you change the headlight mode. Make sure that the last message that you see is Auto.

The headlights will wait about 40 seconds after you exit the car to turn off. Wait a full minute but check that they are turning off. If not, check the smart-stick again. If the smart-stick has the headlights on Auto and they are not turning off, you need to have the car looked at for electrical problems, probably in the switches in the smart-stick in the steering column.

If you have OnStar active, press the black button and ask the OnStar operator to read you the OBD codes, slowly, one at a time, and write them down. Then, post them here.

[CCClarke]

How did you test your battery? A voltmeter is insufficient. If you haven't load-tested it, jump-start your car and head to the nearest brand name auto parts store and ask them to load-test your battery. Better yet, if you can remove the battery and transport it in another vehicle, that would be ideal.

From the symptoms you describe, the battery cannot hold a charge. If the charging system is operating correctly, the battery is highly suspect.

CCC

[Phillip Hastings]

Why is a voltmeter insufficient?

[Göran W]

Why is a voltmeter insufficient?

Think of it as if it vas water running thru a hose. The Volt will tell You the size of the hose. The Amps will tell how high the pressure is. The Ah will tell how much water is available.

No use in knowing the size of the hose if the tank is empty!

[MAC]

Either starter solenoid or loose starter connection. I had a similar starting problem, which was becoming worse and worse. In fact, because of it, I replaced the battery (which was probably still good). I turns out that I decided to replace the intake manifold gaskets because the check engine light was always on and it was emissions related, and the STS has a known problem of intake manifold bolts coming loose. So I removed the intake manifold and decided to replace the starter while I had everything apart. When I went to remove the starter cable (the heavier cable that is not connected to the solenoid, which I believe is ground), it was loose enough that it made me think the intermittent (and getting worse) starting problems were the result of this loose cable. I'm not saying a loose cable is definitely the problem with Edith's car but, from my experience, it is a possibility.

[Cadillac Jim]

Cables??? According to the 2005 FSM, the CTS battery has three ground cables and two power cables. A hazard of this type of cable is corrosion in the plastic over the terminal where it bolts to the battery.

One of the ground cables goes to the chassis, one goes to the engine (possibly near the starter but not necessarily), and the other goes to the main fuse/relay center. One positive terminal goes to the starter, as MAC says, and he saw his loose once.

There is a 30 Amp STARTER fuse in the main fuse/relay center under the hood. If it is cracked, it can cause problems that come and go.

There is a STARTER RELAY MINI in the main fuse/relay center under the hood. It's possible that this relay is flaky.

I don't see anything else in the statring circuit that could cause this. There is the ignition switch itself, the transmission (or clutch, if you have a manual shift) interlock, the wiring, and the security system, but these rarely give problems.