Car will not stay on

Nojuego

Registered
My car will not start without a jump. Even when it does start, as soon as I hit the gas the car shuts off. When it is on, I get no power to the dash except for the battery light. My brother thinks it's the battery but if the battery was dead it should still be able to run off the alternator no? Any ideas as to what could be wrong?
 
If the bat is a total dud, then it can easily mess with the alt. Especially if you have been having battery problems and ignored it. A dying battery can kill and alternator and a bad alternator can kill a battery.

Besides fuses I am betting you have a bad alternator and battery. Good chance they both need replacement.
 
You have to be certain to check your fuses uin the holder in the engiine bay first. Then replace your battery (either with a fully charged or new one). Then go about restarting your car and test the alternator.

Jump starting our cars can at times lead to some problems, and dead alternators and blown fuses can result.
 
I don't see how fuses can have anything to do with it if the car runs while on jumper cables.

Unity is correct in saying that even with a really bad battery (or even possible bad terminals) even a good alternator can't keep the car running.

If you don't have a battery charger to leave on it overnight, use another test battery swap that in like Roadboss suggested or pull it out and take it to an auto parts store to have it tested.
 
Well I checked the fuses, all fine. Replaced the battery but the battery light is still on. I'll change out the alternator tomorrow see how that goes.
 
Ok, stupid question. But which fuses did you check, the mains right? I've been down this road before with another member long ago who insisted no fuses where under the hood. :) Just wanna make sure.

And were the jumper cables ever hooked up in reverse by chance?
 
I believe an explosion would result...

An explosion would be unlikely (but possible) but some shorting out and frying of some wiring/electrical would occur.

Unity said:
Ok, stupid question. But which fuses did you check, the mains right? I've been down this road before with another member long ago who insisted no fuses where under the hood.

There is a fuse block under the hood for high current fuses. Most accessory fuses are inside the car. Both of them should be documented in the owners manual I believe.

Nojuego said:
Well I checked the fuses, all fine.

Again, this I don't see how this could of been a fuse problem. Either a fuse is broken or it is not. Meaning the affected system will either function or not function, there is no in-between or "only while on jumper cables"

Unless I'm mistaken can someone explain to me how an intermittent problem or a problem like this could be a fuse?

Be2lose said:
Why not? I could understand if the altenator is failing also.

The battery is a critical link in the electrical system. If it is shorting out internally or has other problems that don't allow it to function as a physical connection in the circuit for power your alternator can't magically bypass it.
 
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Replaced the battery but the battery light is still on. I'll change out the alternator tomorrow see how that goes.

Did you get the battery tested first? I would get the alternator tested too before just replacing it.

There are a few other items that could be causing you to have a problem, just replacing parts gets expensive fast.
 
Again, this I don't see how this could of been a fuse problem. Either a fuse is broken or it is not. Meaning the affected system will either function or not function, there is no in-between or "only while on jumper cables"

If the fuse between the alt is shot the alt will not supply power to keep the car running or charge the battery. But the battery can supply power to keep the car running just like a jump would. However, since the alt is no longer charging the battery, the car will quickly die.
 
Again, this I don't see how this could of been a fuse problem. Either a fuse is broken or it is not. Meaning the affected system will either function or not function, there is no in-between or "only while on jumper cables"

If the fuse between the alt is shot the alt will not supply power to keep the car running or charge the battery. But the battery can supply power to keep the car running just like a jump would. However, since the alt is no longer charging the battery, the car will quickly die.

That sounds feasible. I didn't realize there was a fuse between the battery and the alternator.

And if a recently jumped battery was removed from jumper cables and the fuse in question was shot it could die.

However, on a side note it drives me crazy when people suggest it has to be a fuse to almost any problem. For example, "my A/C doesn't work all the time, I think it's a fuse." :big-grin:
 
Ok, stupid question. But which fuses did you check, the mains right? I've been down this road before with another member long ago who insisted no fuses where under the hood. Just wanna make sure.

And were the jumper cables ever hooked up in reverse by chance?
I checked all fuses. The ones under the hood and on the side of the dash. All ok. I would probably commit suicide if I ever put on jumper cables the wrong way.

Again, this I don't see how this could of been a fuse problem. Either a fuse is broken or it is not. Meaning the affected system will either function or not function, there is no in-between or "only while on jumper cables"

Unless I'm mistaken can someone explain to me how an intermittent problem or a problem like this could be a fuse?

Although the problem didn't show symptoms of a blown fuse it's never a bad idea to check them anyway whenever there is an electrical problem. It's easy to do and will save you from alot of "duh" type situations.

Did you get the battery tested first? I would get the alternator tested too before just replacing it.

There are a few other items that could be causing you to have a problem, just replacing parts gets expensive fast.

Yes, the battery was tested right after I asked for it. I think the alternator is just not working to full capacity. I drove it to work today with the new battery in and just as I was getting there everything started shutting off. It idled fine just as soon as I hit the brake or gas things started shutting off. First the radio then the climate control then the message center. At the end the message center only came on when the car was idle. That leads me to believe that the alternator is not producing enough power to run everything.

If it was a short, I think i'd be experiencing many more problems like burnt components/wires(I know the smell of burnt electronics well). If some other component is draining too much power from the alternator then there would be either a blown fuse or the smell of freshly baked electrical components. Alternators can produce alot of current and if one of the smaller components was drawing most of that power it'd most likely blow a fuse which would separate that part from the rest of the system.

I have above average knowledge when it comes to electronics although when it comes to car electronic systems I can only rely on the basic stuff I know and have no experience dealing specifically with automotive electronics(besides speakers/radios/etc). I figured i'd ask in case there was another one of those common problems that I wouldn't notice right away. I'm going to replace the alternator tonight once I get a ride and we'll see how it goes.

Thanks for all the help guys.
 
Yeah if it was a short you would most likely be blowing a fuse somewhere too.

Let us know what happens when you replace the alternator. I know a bad alternator is usually pretty easy to diagnosis but from what I hear on these boards it can cause a lot of "odd" symptoms on the Mark VIII.
 
I had the exact same problem with my dash. I had a post in here about it. Nothing in the dash but the battery light. It ended up being my stupid cheap a$$ battery cable clamps. It caused all sorts of problems. Roadboss also had a post on here with what looked like some quality cable clamps. If I knew how to post links I would but I dont. Check your connections to the battery!!!
 
Alternator is in and the beast is running better than ever. The guys at autozone tested the old alternator and it didn't even make it past the first test.
 
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