ej 25 alternator wireing

farquire Commited Dubber

71 posts · joined Jun 2009 · 13 Sep 2014, 9:03 am

#1000131

have the motor in my syncro and running,close but no cigar as yet,its putting out 15.6 v is this too high, alt light is on all the time,have the three wire plug alt black/white to dash light where do the other two wires go, blue/red and black/red also the engine check light should this come on with the ignition and go out once started carn't get it to do anything at the moment
mike

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 · 13 Sep 2014, 1:28 pm

#1000139

Is it a late model engine?

the later alternators are controlled by the ECU as they dont start charging till the engine is upto temp.

there is generally a warning light wire, ECU control wire and voltage sense wire.
Black/white is normally warning light, how have you hooked the other 2?

farquire Commited Dubber

71 posts · joined Jun 2009 · 13 Sep 2014, 5:42 pm

#1000150

its a 2003 liberty motor the other two arn't connected

mackaymanx Custom Title Time!

1,611 posts · joined Jan 2006 · 13 Sep 2014, 6:32 pm

#1000154

This is the label off a 2003 Liberty alternator on the motor I pulled last week.

L - Light
S - Sense
C - Computer

from what I've read leave the C terminal unconnected and it will self regulate.

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mackaymanx Custom Title Time!

1,611 posts · joined Jan 2006 · 13 Sep 2014, 6:36 pm

#1000155

This is exactly the same as the 2005 Liberty alternator. If you hook up the C terminal to power, the alternator will put out 20 volt ( first hand experience with this).

Quote of the week
"Do I wish to send them to you again, nope, no interest can't be bothered really, to much hassle for little or no return."

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Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 · 13 Sep 2014, 7:00 pm

#1000157

farquire wrote:the other two arn't connected

there is your problem, the sense wire needs to connect to the battery positive so it knows what voltage to put out to maintain proper voltage at the battery.

farquire Commited Dubber

71 posts · joined Jun 2009 · 14 Sep 2014, 9:49 pm

#1000215

connected up the sense wire light went out but is out all the time now unless i earth the light wire manually to check the bulb,the black and white seems to have 5-6 volts all the time motor running or not ,i thought it would be negative untill the motor started and alt charge changed it to positive and the light goes out,thats my basic understanding of it,if its negartive all the time the light stays on positive all the time it won't light,have another alt i can try later in the week hopefully it won't do the same thing

farquire Commited Dubber

71 posts · joined Jun 2009 · 17 Sep 2014, 9:59 pm

#1000399

changed alternator all is good, charging at 14.6,dash light goes out as soon as it starts,black and white is light ,blue and red is the sense wire,third on mine is black and red and doesn't appear to be needed,one step closer to driveing it