Removing dead battery

Do not disconnect the positive Or negative cable while vehicle is running it is no longer an acceptable test and damage to computers could occur as there is no ability to suppress or absorb a voltage spike. If you remove the negative cable to check for an amperage draw that's an other thing. You should use a meter and connect it in series between the neg post and the neg cable once all modules are in sleep mode there should be no more than .3v as a rule of thumb. If more you have a parasitic draw which you could isolate the system/circuit by removing fuses one at a time. When the draw is gone that's the circuit in question.

Open the trunk. Lift the carpet and the spare tire/battery cover. Loosen the nut and disconnect the NEGATIVE (BLACK) battery cable. If you are removing the battery, you will have to also remove the positive cable and remove the battery hold-down bracket to get the battery out. But ALWAYS disconnect the NEGATIVE cable FIRST and when you put it back together, connect the negative cable LAST.

There is a problem in the charging system. Either your battery is not holding a charge anymore, or your alternator is dead. The first thing to do is check the alternator. turn on the car and then remove the negative battery terminal. If the car shuts off immediately after disconnecting the battery then your alternator is bad and needs to be replaced. If it stays on, then your alternator is OK, you then need to remove the battery and go have it tested at your local auto parts store. Also have all the battery cables checked for corrosion as well, if they're hard and frayed then replace those as well.

this problem could have a few causes.
the battery clamps are corroded and need cleaning
a loose wire from the battery
faulty starter relay
a weak starter

I would start by inspecting and cleaning the battery posts and clamps also make sure that the clamps are fully seated on the posts and tighened securely.
check the battery and starter wires for signs of wear, such as torn or burned insulation or frayed wire, near connectors.
If cleaning the connections in the charging / starting system does no good then you might need to replace the wires completely.

you could also remove the starter (disconnect the battery first!) and take it to a local parts store such as Autozone for testing.

as for the excessive engine revs, this could be something as simple as needing to add some of the proper type of automatic transmission fluid. after you get the vehicle starting again you should check the transmission fluid level

original posted @ http://www.allfordmustangs.com/forums/2005-2010-v6-mustang-tech/120748-2005-2008-mustang-auto-transmission-fluid-adding.html

"Basically, the drain plug on the transmission has another plug in the center of it. You add fluid and use it to determine if the fluid is filled as it is connected to a tube in the drain pan. They tell you to pump Mercon V transmission fluid into this connection. You will need to get a hose adapter to scew into the center tap and connect a hand pump or electric pump to the hose fitting. When you think you have added enough, disconnect the hose, if you are underfilled, nothing will come out, if you are overfilled then fluid will come out until it drains down to the proper level. Make sure the car is parked on level ground when you do this or you will not get proper results. When removing the center plug, make sure you hold back on the drain plug with an open end or box wrench, or you may end up removing the drain plug and will drain the entire transmission fluid that is in the pan, rather than just checking to see if it is full."

I like to start with the free or cheap stuff and work my way up to more expensive solutions.

so in summary
1.) check clean and reinstall battery cable clamps

2.) check wires and connections on starter as well as any power distribution blocks or
engine / chassis ground.

3.) take starter to parts store for testing, take the battery as well, most can test or charge your
battery in as little as an hour.


Finally, if none of these solutions remedy the situation then you may need a new alternator or serpentine belt.

hope this helps

i just had the same problem...the wrench light means the car is in "limp home" mode and i had to replace my throttle body assy....$165 on ebay at blueovalindustries

Sarah

1. Ensure you are using the correct spec replacement battery.

2. In many vehicles the radios and sound systems will cease to function if the battery is disconnected and require the radio code (supplied with and unique to the vehicle) to be punched in to activate the unit once power is restored.
I am not sure if the 2000 Mustang has this feature.

Make sure you have turned off all electrical functions on the car and remove the key from the ignition.

3. Batteries are dangerous as they emit explosive gasses which can ignite easily with one spark.
Do not change the battery immediately after running the car. Open the bonnet and allow air to circulate for a while before changing. Wear protective eye wear and clothing when working with the battery and remove metal objects such as rings ,watch bands, bracelets etc. as these could accidentally touch a battery terminal and cause a spark. (Be careful as I have personally seen a car battery explode when gas emissions have ignited with a spark).

4. Disconnect the cable from the negative ( - ) terminal first. Using a spanner, loosen the nut on the cable end and gently remove the cable from the battery terminal. You may need to move it around a little on the terminal before it slides up and free. Disconnect the cable from the positive (+) terminal second by loosening the nut and gently removing the cable. Move the cables out of the way and place a plastic cover wrapping over both cable ends so they do not accidentally contact an exposed battery terminal.

To eliminate risk, wrap some plastic electrical tape around the old battery's terminals before removing it. This ensures no accidental contact with metal parts of the car when moving the battery. The new battery should have a plastic protection cap over each terminal. Do not remove these until the new battery is secured and you are ready to re-connect the cables.

5. The battery clamping system will need to be released to remove the battery.

6. Check the metal cable terminals for corrosion (the presence of white ashy material). They will need to be cleaned up before connection to the new battery to ensure good contact.

7. Install the new battery on the battery platform ensuring it is firmly and properly seated and clamped with the clamping system. Ensure it is properly secured before re-connecting the cables.

8. Connect the positive cables to the positive (+) battery terminal first and then the negative (-) second. (The reverse of removal). Do not overtighten the nuts on the cables when clamping them to the battery terminals.

9. I usually run a very light and thin smear of petroleum jelly over the metal cable ends and top of the battery terminal once everything is clean and connected up. Now replace the protector cover (if fitted to your vehicle)) over the positive cable end and you are done .

10. If your car radio is coded, disconnecting the battery will clear the code on the radio so ensure you have the code available to reset the car radio after the battery is reconnected.

whoa !!!! You are playing with a bomb. Disconnect the negative battery cable before trying anything. Then just remove the screws from the rear of the steer wheel that holds it on and carefully disconnect the wires and switch it out. Careful with power on this thing can deploy. The air bag is usually built in to the bag and whole assembly is replaced.

A Battery "DRAW" Test Should be Performed.
TOOL:: >With A 12 Volt Test Light
Disconnect GROUND Cable @ Battery, Connect TESTLIGHT CLIP End to CABLE End And PROBE TO The Battery, The LIGHT SHOULD Come ON.
KEEP IT ON AND MONITERED While Removing 1 by 1 the FUSES In Main Fuse BOX, Untill the Light Goes OFF.
When It DOES you have FOUND the CURCIUT that is Draining your Battery. Take Nessasary Steps to Correct THAT Problem and You Have Fixed the Problem.
THIS IS ALL AFTER INSURING THAT THE BATTERY IS CHARGED AND TESTED. a DEAD CELL IN THE BATTERY will MASK ITSELF WITH THIS TROUBLE DISCRIPTION

Here is the procedure I use to isolate a battery drain. Remove negative battery cable from the battery. Using a 12-volt test light, hook one end to the negative battery post the other end to the negative battery cable you just disconnected. The test light will glow or "light" if there is a drain. If the "light or glow" is faint, that is probably normal draw for the clock or computer. If the "light or glow" is bright, then there is a large drain. That should be corrected. Now start removing and replacing the fuses one by one until the light goes out; that one will be the circuit with the drain. Remember to hold in the button in the door jam for the interior lights.

It's under the car where the transmission meets the back end of the engine, looks like a big juice can with a smaller one stuck to it on top.(battery main cable goes there) Disconnect battery before removing it.Before taking it apart, have the battery tested and make sure that the cable ends and battery terminals are clean!