2004 Chevy Blazer. Twice now in the last 2 weeks it wouldn't start. First time got a jump and it started up fine each time for over a week. Tonight after work, nothing. The radio still worked and the dome light, plus the temp display inside. Lights were dim. Got a jump and it started right up.

So.....could this be an alternator problem causing this?

SUV has 74,000 miles. Battery is about 3-4 yrs. old. I had it replaced when a rear door lock faulted causing the original battery to discharge several times. Alternator has never been replaced before. Also I've noticed using the turn signals and rear defrost causes the battery gauge to drop somewhat when stopped at a red light or stop sign. Turn signals causes the battery gauge to wiggle back and forth.

Thanks for any feed back.

 

What does it do when you try to start it? Turn over, but not fire? Click once and that's it?

It could be a bad battery. That's pretty cut-n-dry as far as testing goes. Most autoparts stores can do a load test. While you're there, they can test the charging system as well.

The reason I ask the first couple of questions is that the ignition switch is notorious for failed contacts on these trucks and it can cause a whole host of weird problems. It's pretty easy to test if you have a multimeter. The info is in the link at the bottom of my signature below. The wiring diagrams are for a 2000 so the colors may be different, but the connector cavities should not be.

 

Just made clicking noises. Didn't try to turn over at all. Battery was brand new in August of '08.

 

They said it just needed a new battery. The charging system was fine. But I still get that drop on the gauge when using the rear defrost (when stopped). Also the fluttering when using the turn signals. Any thoughts out there?

 

Mind if I join the thread as fellow problem sharer

About 30 minutes ago coming home from dinner with the family, I noticed my guage lights are real dim.. turn signal was blinking faster,
At that moment the DC V on the dash == 10V. Less then 1 mile later it had dropped .5 V
Headlights are real dim now. I get home and check the V on the battery and it reads 11.64 V. This coming from a multimeter
I tried to start it and it just clicked really fast, Checked the Battery again and it was 11.34 V.
I was attempting to start it to check the output voltage on the alternator, I figured 11.5 V would start it but I don't know.

I'm guessing it's the Alternator.. What do you guys think?

 

^ Classic Alt. Failure.

Voltage doesn't matter to start, It's amperage that counts. You can't test that with a DMM (digital multi meter) because you have to load test it. R&R alt. Have it tested by an autoparts store but i'm confident that's what it is. Also before starting after replacement make 100% sure your battery has a full charge. Putting a big load like charging a half dead battery on a brand new alternator can cause it to fail.

 

Thanks for the reply Mike, I think so to. But it through me a curveball when it wouldn't start back up, thats a first for me. Then again everything on it is electrical so... I'm gonna go ahead and replace the Alternator with a factory one tomorrow and charge the battery.

Thanks Again Mike!

 

You're welcome. That's what we're all here for.

 

Just like swartlkk said, def check the ignition switch for failed contacts.
Otherwise: Once upon a time a ford I used to own had a bad battery and this told me so.
Unplug your battery while the engine is running, headlights on. Look at your lights when you disconnect the battery, if they get brighter replace your battery it had a dead cell. If the car shuts off replace the alternator or have it tested just to be sure.

 

^^^
its a really dangerous way to test the alt. Dont do it.@bella313 how much drop are you talking about?