battery drain
Elder User
Joined: Aug 2003
Posts: 624
Likes: 0
From: Houston, TX
Originally Posted by Schroder
The one that is drawing the current is yellow and it is hooked to a blue which I beleive is the ignition and then there are also two black wires hooked to it.
Last edited by cookkd; Aug 20, 2006 at 01:28 PM.
Junior User
Joined: Mar 2004
Posts: 72
Likes: 0
From: colorado
on the above post about the alternator diodes being hot when the engine is cool.And I checked it was hotter then hell..but would you say if I disonnect the battery it should be cold ?if I recoonect the battery it will heat up ? So then the alternator is bad ?
right now the alternator puts out 12.8 amp and should be 14 or more..Either a short
is causing the drain or the diodes on the alternator.Would you agree ?
right now the alternator puts out 12.8 amp and should be 14 or more..Either a short
is causing the drain or the diodes on the alternator.Would you agree ?
Elder User
Joined: Aug 2005
Posts: 996
Likes: 0
You have bad diodes in the alternator. these prevent current from backing up from the battery when engine is off. there are six of them and at least one is shorted causing the battery drain and lowered power output.
Replace alternator.
Ken
Replace alternator.
Ken
Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
burned out fusible link indicates there is a high current, greater than current rating of the link, short somewhere in circuit beyond fuse link....either to ground or another circuit...or a device drawing too much current such as a dragging fan motor
Junior User
Joined: Mar 2004
Posts: 72
Likes: 0
From: colorado
New thing with a fully charged battery now dead.But the alt is not hot or warm from what I can tell drained the battery.Can the alt cause all this or the volt reg also ?
it never did it before .Any opinions help full
it never did it before .Any opinions help full
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Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
with fully charged battery pull all other smaller leads off large lug on starter relay that positive red lead from batt. goes to...
tap each one to red battery lead looking for a spark....spark=culprit circuit
none sparking
use DVM current meter and measure current draw of each circuit lead to pos + battery lead
there will be 1 to PCM clock and radio that normally draws less than 10ma with key off.....all others should be zero 0 nada nothing
tap each one to red battery lead looking for a spark....spark=culprit circuit
none sparking
use DVM current meter and measure current draw of each circuit lead to pos + battery lead
there will be 1 to PCM clock and radio that normally draws less than 10ma with key off.....all others should be zero 0 nada nothing
Former ******
Joined: Nov 2004
Posts: 4,901
Likes: 2
From: Salt Lake City, Utah
My suggestion, go to your local auto parts store and have them test your chargeing/starting system. Chances are that this will help locate the source and eliminate several possible culprits.
Junior User
Joined: Mar 2004
Posts: 72
Likes: 0
From: colorado
I did do that and was told it was putting out 12.8 amps they suggested either bad alt.or a short somewhere.After I replaced the battery.put it in it showed a negative draw on the gage.Let it rest and by the next day the battery was completely drained
and this has only bin the last few days.Prior to this no problems indicated.
and this has only bin the last few days.Prior to this no problems indicated.
Postmaster
Joined: Sep 2003
Posts: 4,452
Likes: 1
From: Southern California
Teg3:
One sure way to see if the alternator diodes are bad is to remove the big wire from the back of the alternator, but tape it up well and make sure it does not touch any metal parts. Also, make sure you disconnect the battery before trying to remove that wire, then reconnect the battery after you are done.
If removing that eliminates the drain on your battery, you have a bad alternator. If not, you have to start pulling fuses one by one to see which circuit is causing your short.
One sure way to see if the alternator diodes are bad is to remove the big wire from the back of the alternator, but tape it up well and make sure it does not touch any metal parts. Also, make sure you disconnect the battery before trying to remove that wire, then reconnect the battery after you are done.
If removing that eliminates the drain on your battery, you have a bad alternator. If not, you have to start pulling fuses one by one to see which circuit is causing your short.
Former ******
Joined: Nov 2004
Posts: 4,901
Likes: 2
From: Salt Lake City, Utah
Bad alternator diodes or not, 12.8 amps is unacceptably low. Should be at least 50. At that rate, the power consumption of the vehicle exceeds the alternators output, and the battery will never charge. I would follow the auto parts stores recommendation on this one, the test automatically eliminated other causes, because it checks for alternator load, and stray current. If it had found stray current, their machine would have caught it. You need a new alternator my friend. The only other thing I could suggest is to make sure the battery cables themselves are not corroding inside.
