Eclipse alternator alternator putting out to much power

time to have the battery , alternator tested by an accredited auto electrical shop
batteries test good but fail if a load tester is used and having to jump start it indicates that the battery is not good
If there is not enough power available to run the ECM then it will die when the battery voltage drops below required voltage
the fact that ir runs for a while and dies indicates that the alternator is not producing sufficient power to run the battery and the ECM again indicating a bad battery

Either battery is dead, or a fuse (70A?) in the main fuse box has blown. This is rare, but can happen. A major fault in the alternator, or the alternator harness can blow this fuse e.g the harness burns on the exhaust pipe and shorts to ground.

very rare alt has built in regulator replace alt

You should not have to "remove" anything. Either loosen the alternator, or if installed, use the tensioner to loosin the belt, and put the new one on.
It's a bit easier using the alternator (if easily accessible) cause the tensioner you have to hold up (or down) while pulling the belt off - and gettin' it back on is a bit more difficult this way.
Let me know if you need futher assistance.
carsandcomps,
Guru, Premium Expert @ Fixya.com

sound like bad battery cables.replace them.the positive battery cable is old and have a lot of resistance not allowing power to the alternator to charge battery.if battery cable good check alternator connector wires.make sure they are not damage also check alternator fuse and fuse link.turn off radio before removing battery wires so you wont lose radio code.

The head lights killing the car is a charging problem.Put a volt meter on the car,and check the voltage while the car is running.It should read about 13.65 to 14.25 volts.If it is less than this ,the alternator is not putting out enough voltage,or none at all.If there is 12 volts or a little more when you check it(while the car is running)then the alternator is not charging at all.12 volts is plain ole battery voltage.Check for a alternator fuse that is blown,or any cable or wires loose or come apart.If there is nothing found,then replace the alternator.Be sure the battery cables(cable ends) are clean and shining.Not dull in color,or grey,to black.Also the post on the battery.Put them back on tight.If this helped,please let us know,thank you.

you don't hit the alternator, you hit the starter to help is shake free because it is already going bad. take battery and alternator to parts store and have both tested. check the wires at the starter and make sure they are on SECURELY. very important SOLID CONTACT is occurring. do your lights turn on? check starter relay if the eclipse is equipped with one.

are you handy and able to work with tool. this may be a dumb question but it is necessary. because you need to get under the car and disconnect the wires and unbolt the alternator. aside from losen soem of the fan belt in order to get to the alternator.
my suggestion is go to local lib and lookup the hayes automotive book and see if you can handle it. if so, then read throught it understand what you have to do to get to the alternator and put them back to gether.

if you are capable of all these. you can email me at [email protected]
i can give instruction as how to do it.

Well generally and very basically, ya, unplug the wires from Alternator then remove the bolts that attach it, remove the drive belt, Then, reinstall the new Alternator, then put belt on.. retighten the bolts.. reattach the Wires.. ya should be good to go. Check Check Check.

NB: Take note of how "Tight" the belt drive is and try to replicate that tension when finished.