Running On Battery? (disconect Batt+ Dies)

[dlobi]

Help. Please tell me I won't be trying to trace wires everywhere.

 

With fully charged battery, car runs fine but the battery gets drained.

I removed the alternator and had it checked out, It Passed fine.

If the car is running and I disconnect the battery, it instantly dies.

 

Is there something simple I'm not looking for here?

 

Thanks!

[merlin5577]

Help. Please tell me I won't be trying to trace wires everywhere.

 

With fully charged battery, car runs fine but the battery gets drained.

I removed the alternator and had it checked out, It Passed fine.

If the car is running and I disconnect the battery, it instantly dies.

 

Is there something simple I'm not looking for here?

Thanks!

 

Makes sense, you've broken the circuit. The battery & cables complete the circuit from the alternator to ground. If you could somehow pull the cable off the battery and touch them together fast enough the truck wouldnt (shouldnt is a better word) shut off.

 

Now your problem; If the alternator checks out then most likely you have a short/power draw somewhere and the alternator cant produce enough power to compensate, thus drawing power from the battery. My suggestion is to place a voltometer on the battery with the engine running and start pulling fuses. When you see a voltage or amperage spike, you found your problem curcuit. Good luck.

[minibike132]

If the car is running and I disconnect the battery, it instantly dies.

This is a very bad idea on anything with a computer connected to it. You can send a spike through the vehicle and take any or all of them out. That would be expensive.

 

If you could somehow pull the cable off the battery and touch them together fast enough the truck wouldnt (shouldnt is a better word) shut off.

Nobody should ever ever ever do this. The previously mentioned computers would be a major problem here but what I would worry about more is an explosion. A battery that is charging puts out hydrogen and doing this would create a massive amount of sparks. Sparks plus hydrogen make a dangerous situation.

 

 

How old is the battery, my first thought is a battery that is no longer taking the charge sufficently.

[merlin5577]

If the car is running and I disconnect the battery, it instantly dies.

This is a very bad idea on anything with a computer connected to it. You can send a spike through the vehicle and take any or all of them out. That would be expensive.

 

If you could somehow pull the cable off the battery and touch them together fast enough the truck wouldnt (shouldnt is a better word) shut off.

Nobody should ever ever ever do this. The previously mentioned computers would be a major problem here but what I would worry about more is an explosion. A battery that is charging puts out hydrogen and doing this would create a massive amount of sparks. Sparks plus hydrogen make a dangerous situation.

 

 

How old is the battery, my first thought is a battery that is no longer taking the charge sufficently.

 

 

Probably should have mentioned this. Yes, Sparkstech is right, you can mess stuff up by doing this, but it does work.

 

Hydrogen? Ummmmm...... Last I checked (I could be wrong) modern batteries are sealed, so hydrogen output should be next to nothing. But nontheless it is dangerous.

[minibike132]

If the car is running and I disconnect the battery, it instantly dies.

This is a very bad idea on anything with a computer connected to it. You can send a spike through the vehicle and take any or all of them out. That would be expensive.

 

If you could somehow pull the cable off the battery and touch them together fast enough the truck wouldnt (shouldnt is a better word) shut off.

Nobody should ever ever ever do this. The previously mentioned computers would be a major problem here but what I would worry about more is an explosion. A battery that is charging puts out hydrogen and doing this would create a massive amount of sparks. Sparks plus hydrogen make a dangerous situation.

 

 

How old is the battery, my first thought is a battery that is no longer taking the charge sufficently.

 

 

Probably should have mentioned this. Yes, Sparkstech is right, you can mess stuff up by doing this, but it does work.

 

Hydrogen? Ummmmm...... Last I checked (I could be wrong) modern batteries are sealed, so hydrogen output should be next to nothing. But nontheless it is dangerous.

 

 

 

 

 

 

They are sealed meaning you cannot refill them. They all still have a vent. If you make the mistake of leaving a charger on a battery till it gets overcharged and starts cooking off there is an unmistakeable explosive smell.

 

It's pretty unlikely but why take chances. The more probable effect would be smoking some expensive modules.

[C & A s Dad]

You guys are exactly right about pulling the cable. If it does not fry the ECM/PCM it can easily destroy an alternator. This was a common practice back in the 60s and 70s but really you never see this done anymore and for very good reasons.