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charging system help


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43 replies to this topic

#26 ivans imports

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Posted 28 March 2013 - 09:51 AM

brushes are realy cheap and not to hard to change

#27 Cougar

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Posted 28 March 2013 - 10:05 AM

You can install all the good alternators you want. If the field wire is grounded they won't work either. If you follow the advice I gave you in post 19 it will show you what you need to do to fix this. Using your voltmeter is the best tool you can have to work on this problem.



#28 mikaleda

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Posted 28 March 2013 - 10:59 AM

I agree with cougar, I doubt your problem is in the alt.

#29 Gloyale

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Posted 28 March 2013 - 12:22 PM

Key off:

 

Disconnect ALT wires.  Test you've got full battery voltage on the Main lead (big white) Don't let this wire touch ground, wrap it with tape if needed.

 

Next, turn key on.  Test black/white wire for IG. switched voltage.

 

Now, look inside....BATT light should be off.  Go back up front, and jump the White/red wire to ground.  Look back inside, the BATT light should be on.

 

 

If all that checks out, the wiring is good, and the problem is in alt.

 

I suspect though, that you'll find a problem in the wiring doing this.


Edited by Gloyale, 28 March 2013 - 12:23 PM.


#30 HATCHY

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Posted 28 March 2013 - 07:19 PM

Ok so I disconnected the plug on tbe alternator. And battery light and all other guage lights are off. . So from what I'm gathering is that this is a problem in the wire.. looked the plug was a little gummed up too. I'm going to work on that. Thanks for the help fellas.

Cheers

#31 Cougar

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Posted 28 March 2013 - 07:47 PM

The warning lights should turn off when you disconnect the plug to the alternator since the ground for those lights is made inside the alternator. We wanted to make sure that the wire didn't have a ground on it when the wire was disconnected and the light would stay on if there was a ground on it. When the alternator is working voltage is generated on that wire so it isn't at ground potential anymore unless the alternator has a problem. You already stated the battery warning light turns on with the key so it looks like the alternator is the problem here even though you tried others. LIke I stated earlier, both of the wires on the back side of the alternator should have close to battery voltage on them when the alternator is working. 



#32 Cougar

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Posted 28 March 2013 - 08:01 PM

Pretty sure burned out battery bulb wouldn't cause the car to not charge. I dint believe I even have a voltage regulator either. The 78 brat has one and the 81 wagon . But 85brat doesn't. And my standard I don't think has one either. Pissing me off I'm ready to drive it again.

 Having a defective battery warning light will indeed disable the alternator ( I learned about "the warning light" the hard way many years ago working on a Ford truck. Many hours were spent in trying to find out why the alternator wouldn't work). The field is charged up using current through that lamp. If there is no field current you have no charging action. The newer alternators have the voltage regulator build inside them. They are electronic instead of the older external relay style.



#33 ivans imports

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Posted 29 March 2013 - 09:15 AM

seen a lot of bad alts this year at least 8 recently all alt problems mostly brushes and regs i doubt that a dead batt light whould cause no charge as the wire harness is spliced were it gos to light the light branches of the signal feed. on non internal reg cars mabee but not on internal reg cars



#34 Cougar

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Posted 29 March 2013 - 04:24 PM

Power to the warning lights comes from the ignition switch. The return side of the lights tie to the proper spots but they also are diode isolated and tied to the field winding of the alternator, along with the battery warning light to work in the test mode KOnEOff. Pull out the battery warning light and see what happens to the charging voltage. Then you will believe.



#35 Gloyale

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Posted 30 March 2013 - 01:01 PM

Ok so I disconnected the plug on tbe alternator. And battery light and all other guage lights are off. . So from what I'm gathering is that this is a problem in the wire.. looked the plug was a little gummed up too. I'm going to work on that. Thanks for the help fellas.

Cheers

 

No....you didn't read carefully.  With the plug disconnected = no light. 

 

Key on, Eng off.......plug disconnected..............Jumper the WHITE/REDstripe wire to ground.........THEN the battery light should illuminate.  If it does not.....then, there is a problem.

 

And did you test for 12v from Ig. on the Black/white stripe wire?  Should be 12v with Key on.



#36 Gloyale

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Posted 30 March 2013 - 01:04 PM

i doubt that a dead batt light whould cause no charge

 

Yes, it will.

 

One thing EJ swaps will teach you over time is EXCACTLY how to set up the charge system.  It does absolutely need the light, or at least something with a load, on that circuit.



#37 mikaleda

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Posted 30 March 2013 - 01:11 PM

Yes, it will.
 
One thing EJ swaps will teach you over time is EXCACTLY how to set up the charge system.  It does absolutely need the light, or at least something with a load, on that circuit.

+1 that's how i learned, kinda. I learned by putting an ej alt in my ea engine.

#38 Cougar

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Posted 30 March 2013 - 02:42 PM

I've said it before and I guess I'll say it again, the ignition power supplies current to the alternator field windings through the battery warning light bulb filament, which is in series with the alternator field windings. If you open a series circuit (remove the warning bulb) all the current in the circuit will stop flowing and so the field windings will not be able to keep the field up to excite the stator windings. No excited field in an alternator equals no power output from the alternator. There's nothing wrong with the alternator, it just needs to have power to get the exciter field built up and get the action going. As far as I know all Soob models use this design.



#39 ivans imports

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Posted 31 March 2013 - 10:52 AM

mine has a charge gauge no light i'm shure the last harness i cut down had a splice in the white and red wire that trigers the alt feild wire mabee was added but was taped up in the back of dash harness was on a 89 chaser with full gauge pakage. we had cut entire harness down to drop wheight. I will pull the bulb on my 81 brat and see if still charges or my 84 wagon with 2.5. Mind you non have stock alt. I use a mitsubishi delta wound alt is 100 amps and very durabble



#40 mikaleda

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Posted 31 March 2013 - 11:19 AM

mine has a charge gauge no light i'm shure the last harness i cut down had a splice in the white and red wire that trigers the alt feild wire mabee was added but was taped up in the back of dash harness was on a 89 chaser with full gauge pakage. we had cut entire harness down to drop wheight. I will pull the bulb on my 81 brat and see if still charges or my 84 wagon with 2.5. Mind you non have stock alt. I use a mitsubishi delta wound alt is 100 amps and very durabble


Any alt is going to need power going to the feild wire, unless you have a self igniting voltage regulator in it. The white wire with a red chase is the charge light wire on externally regulated subies, I know this because I had to tie into it on mine when I wired the alt into my gl to get it to charge.

#41 Cougar

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Posted 31 March 2013 - 03:37 PM

Any alt is going to need power going to the feild wire, unless you have a self igniting voltage regulator in it. The white wire with a red chase is the charge light wire on externally regulated subies, I know this because I had to tie into it on mine when I wired the alt into my gl to get it to charge.

I concur with you mikaleda. Whether the current for the field comes through a lamp bulb, a current meter, or external regulator, power needs to get to the exciter for the action to happen.



#42 1 Lucky Texan

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Posted 31 March 2013 - 04:28 PM

I think the ECU on 00-04 (?) H6es maybe handles the field current so, perhaps some OBDII/newer cars use the ecu for field current?

 

anyway, I assumed due to the age of the vehicle in the OP, it was probably supplied thru the bulb.



#43 Cougar

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Posted 01 April 2013 - 03:05 AM

You're right 1LT. The newer vehicles, or some at least, have three wires going to the back of the alternator instead of the usual two. The third wire does go to the ECU.



#44 ivans imports

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Posted 01 April 2013 - 10:12 AM

well turns out the brat uses the electric choke curcit to power the alt my doing not subarus to power the mitsubishi alt the buggy runs a 2001 h6 alt is self enegiseing it charges with no wires hooked up has been thiss way for 4 years i does charge high about 15 volts but is race car so dont mind. I gess when nothing is stock is not the same as everyone eles car






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