Alternator or Battery problem? 2007 Expy EL Ltd

[clattin]

Went out a couple mornings ago and the battery was stone dead. Put my charger on it for an hour or so and it started right up. I let the truck run for another hour or so and drove it some that afternoon without any troubles. Friday morning, it started right up again with no problem. Saturday morning, my wife calls me and says its stone dead again. I have her put the charger on it and it charges up and runs ok.

How can I tell if the problem is the battery not holding a charge or the alternator not functioning properly?

As a side note, at the same time the battery first died, the rear window wiper quit working. Don't know if its somehow related or not.

Thanks!
Chris

 

[GaryH2]

I also have an 07 Expy. It was quite strange when my battery went. The truck was stone cold dead. Nothing. Jumped and ran fine all the way from VA to DE. Died cold at the DE I-95 rest stop. Jumped and made it home to PA fine. New battery and no problems since.

If you don't see your headlights flickering or any electrical abnormalities (headlights brightening when the RPMs increase, funny noises, etc...) then I would replace the battery, especially if its the original one.

 

[stamp11127]

Check the alternator output, should be @14v with engine running at idle. If it passes have the battery load tested.
Most likely the battery is toast.

 

[1997SCEBFEX]

+1 on battery. the fact that you've been able to charge it up for 'restoration' leads me to believe its time for a new one.
on the two alternators I've replaced, when they went, all the gauges flickered on/off and nothing electrical would work correctly.

PanHandler.

 

[dariod]

Take the battery out of truck and take it to autozone they will check it for free.

 

[stamp11127]

FYI - I've had batteries "tested" by Autozone with their electronic tester that have shown good, test with the old style toaster type and they are bad. I don't have faith in their testers, plain and simple. Have a real load put on the battery then test.

 

[CJ0920]

Check the voltage on the battery. Crank the truck and see what the voltage is while the truck is running. If you see it go up to about 14 usually 13.8 or so you know the alternator is doing its job. Just like others said, have the battery tested. Doesn't cost nothing to have it done by advanced or autozone. Each battery I've had tested, they run a load on it and will tell you if its good or bad.

 

[911jason]

If you end up needing a battery, I'd highly recommend Costco batteries. After quite a bit of shopping around, their batteries were right down with the least expensive, but have some of the best specs and a 100-month warranty. They also come with a no-questions asked 3-year return (or exchange?) policy.

 

[mtondreo]

pretty sure you can get the vehicle running and then just unhook the negative on the battery. If the truck stays running - then its the battery. If it sputters and dies - it is the alternator and may have taken the battery out also. Hopefully someone can help here and say if that technique still works. This is of course if you dont have a multimeter to check the output of the alternator.

 

[toms89]

pretty sure you can get the vehicle running and then just unhook the negative on the battery. If the truck stays running - then its the battery. If it sputters and dies - it is the alternator and may have taken the battery out also. Hopefully someone can help here and say if that technique still works. This is of course if you dont have a multimeter to check the output of the alternator.

I have always understood this to be a bad idea. The battery balances or is sort of buffer for the voltage coming from the alternator. (Even if its dead) With out it you can get voltage spikes damaging the electronics. Also the voltage from the alternator is a/c converted to dc so its not a very steady or smooth dc voltage.

When you consider all of the electronics in these today its not worth the risk IMO. Most electronics don't do well with voltage spikes.