Battery going dead overnight - Page 2 - 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 Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > Battery going dead overnight

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineRockridge 4WD IS Taking Zone Offroad Suspension Lift Kits Rough Country Jeep Suspension Deals at Rockridge 4WD!

Reply
Unread 02-10-2011, 09:00 AM   #16
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
Heres the latest....
I have pulled every fuse and relay one at a time in or on the Jeep with these results...
50 amp Fuse in the under the hood JB stops the drain when pulled...
IOD fuse under the Hood drops the drain down from 180ma to around 80ma...
The #7 fuse on the inside fuse block drops the drain down to around 11ma...
Pulling the white connector off the BCM which was replaced drops the drain down to 11ma also...
I pulled both door modules one at a time and when each was unhooked the drain went from 180ma down to around 130ma for both sides....

Another question.. is there supposed to be a 50ma current to the door modules when everything is cut off?
Still looking for the answer...
Thanks!

BackBrakeBilly is offline   Reply With Quote
Unread 02-10-2011, 09:06 AM   #17
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
Quote:
Originally Posted by BackBrakeBilly View Post
Heres the latest....
I have pulled every fuse and relay one at a time in or on the Jeep with these results...
50 amp Fuse in the under the hood JB stops the drain when pulled...
IOD fuse under the Hood drops the drain down from 180ma to around 80ma...
The #7 fuse on the inside fuse block drops the drain down to around 11ma...
Pulling the white connector off the BCM which was replaced drops the drain down to 11ma also...
I pulled both door modules one at a time and when each was unhooked the drain went from 180ma down to around 130ma for both sides....

Another question.. is there supposed to be a 50ma current to the door modules when everything is cut off?
Still looking for the answer...
Thanks!
P.S. I have also pulled the Headlight/Dimmer switch, the rear defogger switch, the rear wiper switch, and the VIC display and none had any effect on the drain...
BackBrakeBilly is offline   Reply With Quote
Unread 02-10-2011, 10:20 AM   #18
smokeyeager
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Wilmington, North Carolina
Posts: 214
I'm not sure how you are pulling your readings so I'm going to assume you unhooked the negative cable then hooked the meter between the negative cable and the negative terminal. There should always be around a .50 draw there, anything more is suspect. You have to be sure the bcm is turning off (going into sleep mode) before testing so hook it up and wait 30 minutes, if the reading is still the same jump a wire between the leads on the meter and wait for it to show a drop which is the vehicle going into sleep mode. Remove the jumper if you had to do that and start pulling the lower amp interior fuses first.

From what you have posted it sounds like your testing with the bcm still awake. The diagram I found shows the bcm running off a 20amp circuit breaker. It also shows the #7 fuse running to the headlight switches and the daytime running light module. Double check the headlight switch, the beam select switch (low beam/high beam on column), the headlight delay module, the daylight running light module, and possibly the fog light relay. From what the diagram I found shows those are the only things receiving power from the #7 fuse.

The door modules should stay hot with a slight charge to facilitate lock functions and alarm functions. I added the diagram I found but not sure it'll be big enough for you to read. Shoot me a pm if you have any trouble getting the full size version and I'll get it to you via email or such. Good luck.

__________________
Own a Grand Cherokee? Click Here. [URL="http://www.jeepforum.com/forum/f197/jeepforum-grand-cherokee-member-locations-1162687"]http://www.jeepforum.com/forum/f197/jeepforum-grand-cherokee-member-locations-1162687[/URL]
smokeyeager is offline   Reply With Quote
Unread 02-10-2011, 10:25 AM   #19
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
Thanks!
I'm heading outside right now to do some more checking, Hopefully today will be a lucky day!
BackBrakeBilly is offline   Reply With Quote
Unread 02-10-2011, 11:56 AM   #20
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
Next....
Checked the headlight circuit (Switches and relays/fuses) and again no effect on the current drain...
Started retracing my steps from the start...#7 fuse as before stops the drain, Pulling the white connector off of the BCM stops the drain in both the old BCM and the New BCM, with everything hooked up the drain has been a constant 180ma which is normal for the BCM when its awake but it would seem that the BCM wasn't going to sleep like it was supposed too. Now with everything plugged up like it should be when I unplug the bottom plug on the BCM and wait 30 seconds the BCM is going to sleep and the drain drops down to 15ma...
I think I am getting close to the problem but still not there...
Is there a good wiring diagram to tell me what the wires on the little bottom plug feed?
and just for the record, I want to thank everyone for all the help...
You folks rock!
BackBrakeBilly is offline   Reply With Quote
Unread 02-10-2011, 12:43 PM   #21
smokeyeager
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Wilmington, North Carolina
Posts: 214
It sounds like you have a small drain causing the bcm to not go to sleep. Maybe these will help. 37-41 less 38(1997 only)







__________________
Own a Grand Cherokee? Click Here. [URL="http://www.jeepforum.com/forum/f197/jeepforum-grand-cherokee-member-locations-1162687"]http://www.jeepforum.com/forum/f197/jeepforum-grand-cherokee-member-locations-1162687[/URL]
smokeyeager is offline   Reply With Quote
Unread 02-10-2011, 01:52 PM   #22
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
Quote:
Originally Posted by smokeyeager View Post
It sounds like you have a small drain causing the bcm to not go to sleep.
This does seem to be the case. I have checked several times and it would seem that as long as the small plug that goes into the BCM is unplugged the BCM will act right and go to sleep like it supposed too!
I know that the auto entry lights (but the Interior light swtich still works the interior lights) and the chimes are fed by that plug but not sure what else but something in one of these circuits is not letting the BCM go to sleep...

Can anyone tell me what other things are fed off that plug???
BackBrakeBilly is offline   Reply With Quote
Unread 02-10-2011, 03:41 PM   #23
JS97ZJ
Registered User
1997 ZJ 
 
Join Date: Dec 2009
Location: Dingmans Ferry, PA
Posts: 1,982
Fuse #7 is hot at all times providing power to the BCM that would monitor all interior functions.
Someone posted a thread with nothing to due with your situation but described a problem he had previously with his battery draining.
The out come was with either the liftgate ajar or the flip glass ajar switch being defective. He wasn't sure but disconnected the the wiring to the gate and it solved the problem.
The wiring diagram above is a very simplified version of what's really in there. The actual schematic goes on for pages and is prohibited to post (so I hear)
I'll check back later................
JS97ZJ is offline   Reply With Quote
Unread 02-10-2011, 10:10 PM   #24
JS97ZJ
Registered User
1997 ZJ 
 
Join Date: Dec 2009
Location: Dingmans Ferry, PA
Posts: 1,982
bmc2.jpg

BCM Connectors
JS97ZJ is offline   Reply With Quote
Unread 02-11-2011, 12:02 AM   #25
phitmein
Web Wheeler
 
phitmein's Avatar
1995 ZJ 
 
Join Date: Feb 2009
Location: Columbia, SC
Posts: 1,932
Have you done a load test on your batt. yet ???

I have spent many hours before on drain issues, only to find out I had a bad cell ...

Phit
phitmein is offline   Reply With Quote
Unread 02-12-2011, 09:52 AM   #26
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
Yep, I have had the battery checked a couple of times and even had them put a new one in it just to make sure and then the new one was checked also...LOL
I saw the thread about the "Lift Gate" problems and checked it but I am going to recheck it today....
Its down to those 10 wires that come off of the small bottom plug on the BCM...
Thanks for all the help so far and feel free to keep sharing those thoughts, maybe one will be the simple fix I am looking for! ;-)
Still looking for now though...
BackBrakeBilly is offline   Reply With Quote
Unread 02-12-2011, 12:32 PM   #27
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
FOUND IT!

After checking the Lift Gate Glass latch again it seems that the "Ajar" switch is where the short is!
Took it loose and the drain is gone....
The good thing is during my hunt for the BCM I found a great cheap salvage yard with LOTS of good cheap Jeep parts ($16 for a working BCM)! The switch I need is waiting for me! lol
Thanks again everyone for all the help!
BackBrakeBilly is offline   Reply With Quote
Unread 02-12-2011, 12:41 PM   #28
smokeyeager
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Wilmington, North Carolina
Posts: 214
Quote:
Originally Posted by BackBrakeBilly View Post
FOUND IT!

After checking the Lift Gate Glass latch again it seems that the "Ajar" switch is where the short is!
Took it loose and the drain is gone....
The good thing is during my hunt for the BCM I found a great cheap salvage yard with LOTS of good cheap Jeep parts ($16 for a working BCM)! The switch I need is waiting for me! lol
Thanks again everyone for all the help!
Good deal! I figured it was something like that actually causing the BCM to not power down.
__________________
Own a Grand Cherokee? Click Here. [URL="http://www.jeepforum.com/forum/f197/jeepforum-grand-cherokee-member-locations-1162687"]http://www.jeepforum.com/forum/f197/jeepforum-grand-cherokee-member-locations-1162687[/URL]
smokeyeager is offline   Reply With Quote
Unread 02-12-2011, 11:39 PM   #29
phitmein
Web Wheeler
 
phitmein's Avatar
1995 ZJ 
 
Join Date: Feb 2009
Location: Columbia, SC
Posts: 1,932
Very nice detective work there, well done Sir ...

Phit
phitmein is offline   Reply With Quote
Unread 02-13-2011, 01:42 AM   #30
BackBrakeBilly
Registered User
 
Join Date: May 2004
Location: Tennessee
Posts: 30
Thanks again guys!
Couldn't have done it without y'all!
BackBrakeBilly is offline   Reply With Quote
Reply
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.