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Discussion Starter · #1 ·
I made a thread about this a while ago, back then it wasent as urgent. Now it is. our original idea was that it was the regulator in the alernator. I recently swapped the alternator with a used alternator i had from another motor wich had 90k on it.

And i still get the same results, when i test the system im charging over 16 vts and the battery indicator light is on. I dont know what else it could be.. could it be possible this other alt has a bad regulator?
or is there something else that could result in overcharging?

95 626 V6 ATX

Also the CEL comes on, but not till after the engine is fully warm. I havent checked it but im guessing its probaly an 02 sensor.
 

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that definitely sounds like a voltage regulator to me. however improbable, it is possible that you simply put two defective units on the same engine.
 

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Sounds like your alternator is full fielding. The only way to tell is test the amp output. I'm not sure what the max. AMP output for the mx6 alternator is.

I don't know if the voltage regulator can be replaced or if you just replace the whole alternator? I would assume just the voltage regulator can be replaced.


This is what you need:D

 

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Discussion Starter · #4 ·
I got a snap on Charger/ Tester Unit, very top of the line. I have alot of readings, but basically simply put its over charging.
I guess im going to be bringing the old alternator and the car into a electric shop and have them check both out.

if all else fails, i guess its safe to get a massive sound system to drown out some of that extra power:)
 

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Yes, the regulator is bad. No, you can't replace it (well you can, but its cheaper to just get a new alt). Although its been a while since i've looked at the 6's wiring for it, but I've seen some cars with internal reg.s where the regulator had different wiring than the alt, so you may wanna look at that as well. And 100 amps=output, if i remember right.
 
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That testing system is way to much $$$... But I believe you can pick an analog one up cheap.

The main concern would be over charging you battery. Does it smell like sulfur? You don't want the battery to get over 125F, it could explode.

You should be able to replace the regulator.... the real problem would be taking out alternator out. I looks like a total bitch to do.:tdown:
 

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I have the same problem too. My battery light comes on whenever idle or when driving. It is wierd though because i just changed the battery. I do know however that my alt pushes out close to 14V in less than 30 seconds.

I am guessing thats not good
 

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KING6 said:
i dont need a tester. Also ive taken the alt out before, its not a big deal just drop the A/C compressor and walla.

I just find it hard to believe this alt is bad to. It has to be something with the car.

16 volts is way to high, its most likely that your amp output is max too. Its best to get this problem fixed right away. The battery could explode.

Testing a regulator is easy to do, all you need is some aligator clips, a light bulb, and some wires. You do need a charging system tester so you can put a load on the curcuit. Thats why I suggested it earlier.

I don't see what could cause this in the car. The regulator controls alternator output. It sounds like the regulator is sending full battery voltage to the field ( full fielding) The alternator should not be allowed to full field for a long period of time. It could cause damage to other components in the in the alternator.

If its a piece of cake to pull then do that and take it to the pro's. They can bench test the alternator for you.

Good luck
 

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Discussion Starter · #12 ·
i have a battery tester to put a load on it, it holds as much load as i can give it with out frying anything. The max it will drop is 12vt.

The amp rating coming that the alt is using is 40-50 or putting out, i believe the amp output for our alts are 90.

Also the battery is new direct replacment.

What i dont understand is, if it is overcharging.. the battery doesnt get hot, doesnt get even warm. Also no acid smells or bubbles. And ive been driving it for 2 days now about 50 miles total, and its been running outside my work for atleast 10 min each time to warm up.
 

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i had a problem running 15+ volts with crappy grounds.. the strap on the tranny was left off accidentally, and the other braided strands were in piss poor condition. ran soem 8awg to new, clean chassis spots, in all the common areas (tranny, starter, heads, alt, fusebox, and rear crossmember) and it cleared up the issue. That alternator DID eventually go bad - so it might have been compound.. but wouldn't hurt to try.
 

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That is strange because if the alternator was full fielding your batteries would smell real bad... and get real hot. They could even melt and disfigure.

I don't know what would cause the alt. volts to go so high but the amps to stay lowish.

If you hook a battery chager up to the batteries while the car in ON and you take an amp reading off the alternator, the total amp output should be below 10amps.

You would be tricking the regulator into thinking the batteries are charged, so amp output should be low. If the reading is over 10amp then the regulator is not working properly. I dont know what type of charger you have but it should be able to charge at 20 to 40 amps... no trickle chargers.
 

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KING6 said:
I got a snap on Charger/ Tester Unit, very top of the line. I have alot of readings, but basically simply put its over charging.
I guess im going to be bringing the old alternator and the car into a electric shop and have them check both out.

if all else fails, i guess its safe to get a massive sound system to drown out some of that extra power:)
meh just throw like 4 jls and some amps to match and POOF no more overcharging :D
 
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