over charge - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > over charge

Zone Offroad Body and Suspension Lift Kits, Brackets, DiscToxic Brakes - 3000 PSI Braided Stainless Steel Brake LineRugged Ridge Modular XHD Snorkel Now for both 3.8L and 3.6

Reply
Unread 08-09-2011, 08:18 PM   #1
muddy94yj
Registered User
1994 YJ Wrangler 
 
Join Date: Aug 2011
Location: loveland, ohio
Posts: 19
over charge

i have a 94 yj and i just replaced the ecm in it and now the check engine light is on and it is over charging... it was running at 14 and now it is almost to 19 if i dont run the heater and lights..... can anyone lend me a hand....thanks

muddy94yj is offline   Reply With Quote Quick reply to this message
Unread 08-09-2011, 11:03 PM   #2
deathtrap
Registered User
1993 YJ Wrangler 
 
Join Date: Jun 2011
Location: Hemet, CA.
Posts: 335
check and see what code you have. but if it wasnt over charging before you replaced the pcm you probly
got a bum one. the voltage regulator is in the pcm on these. other possiblity is a shorted to ground field wire
Hope this helped.
deathtrap is offline   Reply With Quote Quick reply to this message
Unread 08-10-2011, 07:24 AM   #3
pasinbuy
Registered User
1994 YJ Wrangler 
 
Join Date: Feb 2007
Location: florida
Posts: 3,840
Fix it right away, in fact do not drive it or you may burn out components or blow your battery with the over charge.
pasinbuy is offline   Reply With Quote Quick reply to this message
Unread 08-10-2011, 09:34 AM   #4
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 15,157
That is no joke. You are full fielding the alternator and it is dangerous. You can boil the battery and it can explode. Do not drive it unless you totally disconnect the alternator!

You either have a bad ECU or a short in the control line from the ECU to the alternator.
Here is a link to pic of the charging system laybackman posted. Disconnect the battery and check the resistance of that wire going from the ecu to the alternator to ground and see if its shorted If it is then pull the ecu connector and see if it is still shorted.
Que89YJ is offline   Reply With Quote Quick reply to this message
Unread 08-10-2011, 04:08 PM   #5
muddy94yj
Registered User
1994 YJ Wrangler 
 
Join Date: Aug 2011
Location: loveland, ohio
Posts: 19
thanks for the tips..... i thought there were 2 voltage regs.... 1 in the ecm and 1 in the alternator..... i am pulling the alt and having it checked... im also going to do the tests that Que89 suggested
muddy94yj is offline   Reply With Quote Quick reply to this message
Unread 08-12-2011, 08:52 AM   #6
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 15,157
Here is the link I should have posted.....blonde isn't a hair color...it's a state of mind.

http://www.jeepforum.com/forum/f12/c...gurus-1123014/
Que89YJ is offline   Reply With Quote Quick reply to this message
Unread 08-18-2011, 06:47 PM   #7
muddy94yj
Registered User
1994 YJ Wrangler 
 
Join Date: Aug 2011
Location: loveland, ohio
Posts: 19
i fixed my over charge problem.... i did a ecm voltage reg bypass and installed a external volt reg..... it works like a charm
muddy94yj is offline   Reply With Quote Quick reply to this message
Unread 08-18-2011, 07:18 PM   #8
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 15,157
So the ecm was just grounding the alternator control? The voltage regulator was a problem on the SMEC modules that Chrysler put in the cars in the 80's. I'm glad to here it's all good now. In my testing I've seen the batteries blow apart from full fielding. Where did you get the regulator from?
Que89YJ is offline   Reply With Quote Quick reply to this message
Unread 08-18-2011, 09:27 PM   #9
muddy94yj
Registered User
1994 YJ Wrangler 
 
Join Date: Aug 2011
Location: loveland, ohio
Posts: 19
i got it from smyth auto parts along with the pig tail for it
muddy94yj is offline   Reply With Quote Quick reply to this message
Unread 08-18-2011, 09:36 PM   #10
muddy94yj
Registered User
1994 YJ Wrangler 
 
Join Date: Aug 2011
Location: loveland, ohio
Posts: 19
this is where i found out i could do it pirate4x4.com.... and this is where is got the how to http://www.thedieselgarage.com/forum...ad.php?t=58251


i dont do to much of my own car repair(untill now...lol) so i had to get the instructions on how to wire it up
muddy94yj is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 02:32 PM   #11
BIGEARS270
Registered User
1984 CJ7 
 
Join Date: Oct 2011
Location: Ft. Collins, Colorado
Posts: 5
I am having a overcharging problem with a 86 Cherokee with a 2.5. I have replaced the battery and the alternator with no change. Now that it is overcharging the engine will spit spuder then die. If i pull the field wire off it runs perfect. Will the above suggestions checking the resistance on the fielding wire or replacing the ECM be the same for this vehicle or is there something i am overlooking?
BIGEARS270 is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 04:46 PM   #12
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 15,157
No, your alternator is internally regulated
Que89YJ is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 09:07 PM   #13
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 15,157
If you are overcharging you need to replace the alternator. Look up the cs-144 mod. It is the same thing for you with an early 4.0 with a renix controller.
Que89YJ is offline   Reply With Quote Quick reply to this message
Unread 06-19-2013, 09:44 PM   #14
Duncan542
Registered User
1995 YJ Wrangler 
 
Join Date: Jun 2012
Location: Petersburg, Illinois
Posts: 128
Make sure it has a good ground on the alternator. If you have a bad ground it will keep overcharging and burn up the regulator.
Duncan542 is offline   Reply With Quote Quick reply to this message
Unread 06-28-2013, 02:55 PM   #15
BIGEARS270
Registered User
1984 CJ7 
 
Join Date: Oct 2011
Location: Ft. Collins, Colorado
Posts: 5
I was trying to gather as much info and parts possible. The jeep belongs to my grandfather who lives more then an hour away from any parts stores up in the mountains. With all the info from the good people on this site we went through everything again and it ended up being the ecm. Runs great again!
Thanks!
BIGEARS270 is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.