Low voltage (Battery Light On)

[mitclipsegs96]

Ok, I've bought this 96 Eclipse GS in January. The battery light was one, along with the check engine light and SRS light. She said the battery light was one because of the battery terminals are messed up. I took it to advance and got my battery tested and it was bad so I bought a new batter and new terminals. After all this the light continued to stay on so I got the alternator tested and it was working right but my system was running at a low voltage.

I’m thinking it’s the voltage regulator but if I’m correct isn’t in the 420A motors the voltage regulator isn’t in the alternator, it is in the ECU.

If it is the voltage regulator do I have to replace the whole ECU or do I just replace the voltage regulator. Advance sells just a voltage regulator for $150.

Also, it being a 420A I know it is not going to be a fast car so I am making it more a show and cruising around car so I’m putting a system in it. I was looking at getting a higher output alternator. Could I just get an alternator with a voltage regulator in it like most alternators or does it still have to wire up to the computer.

Last question, would an alternator for the turbo eclipses still work and someone said something if I’m not mistaking that the 4G63 voltage regulator is in the alternator, or did I mishear.

Thanks in advance.

 

[92AWDHX40]

Check your altenator, wiring battery a lot going on here. Altenator for the car you have stick to that and keep it simple 420 or 4g63.

 

[95gsttsi]

I'm not sure about the 420a if the alternators are different or not but on a 4g63t there's a plug and two power hook ups! That could be a problem check your wiring too! I had a charging problem too

 

[19Eclipse90]

It isn't absolutely necessary to replace the PCM if the voltage regulator gives out. A cheap and easy solution is to wire in an external regulator that bypasses the original, internal regulator. Here's some threads/posts that should be helpful:
http://www.dsmtuners.com/forums/420a-bolt-tech/365914-anyone-tried-external-voltage-regulator.html
http://www.dsmtuners.com/forums/420a-engine-management/296266-ecu-houses-voltage-regulator-420a.html
2GNT.com Forums - Viewing topic #29260 - I just solved my low voltage problem
http://www.electromotive-inc.com/pdf_files/neon99.pdf -- Around page 15 is good, found from this thread.

 

[mitclipsegs96]

Well I know it is not the alternator its passed 3 times at Advance and 2 times at Auto Zone. Right now I am in another state but when I get back I am going to be doing the big 3 upgrade to help with the sound system I am putting in it.
If it is my voltage regulator why can't I just use a 4G63 that has the voltage regulator built into the alternator.
If I get an alternator I have to up date it to a 180 Amp alternator.

 

[94 Talon DL]

have the same problem in my car, although i have no issues with any of the electical system the lights are on. i find that they actually get brighter with higher electrical loads. such as when i turn on lights wipers stereo, ect. and go away when i rev the engine to spin the alt at higher speeds. im not sure if its an internal grounding issue or something like a short but not a dead short.

 

[coryd21]

It could also be a wiring issue between the battery and the alternator. If the signal to the alternator from the battery is at a high voltage then the regulator will lower the output voltage to the battery when in reality the battery is loosing charge over time and being that the alt is putting out a low voltage due to a false signal then it will continue to kill you battery.