Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: delboy259 on December 11, 2015, 03:24:55 PM

Title: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: delboy259 on December 11, 2015, 03:24:55 PM
Hi All.
Just a quick question to the learned folk on here.
The battery on my GC goes flat after about 3 days.
I have done the amp test and found that it has a 1.8amp draw on it.
I have pulled the fuses and found that if I pull the Cluster fuse the drain drops to 0.8 amps.
After some research I found that this is related to the BCM.
Is this correct? and if it is the problem. Would an 0.8amp draw be acceptable.
Any info greatly appreciated.

Derek
Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: bigjeepzj on December 11, 2015, 07:27:49 PM
ZJ's are a pig for flattering battery's
never checked just disconnect the   when not in use
Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: Mike Pavelin on December 11, 2015, 07:45:49 PM
They draw at least half an amp when idle
When testing for a draw, pull the IOD fuse, lock it up and give it several minutes for the computers to shut down before getting a final reading.
Official batery life is about 3-4eeks when parked as long as the battery is in top condition. The handbook stated you should remove the IOD fuse when parking for long periods.
Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: bisleywrangler on December 11, 2015, 11:16:02 PM
I had a similar fault, battery flat after a few days of no use. The drain ended up being a sticky brake light switch so was only staying on occasionsly, draw should be less than 0.1A under normal locked mode.

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Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: Mike Pavelin on December 12, 2015, 08:50:31 AM
draw should be less than 0.1A under normal locked mode.

Not on a ZG, they were always very high, hence the need to pull the IOD fuse.
Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: bisleywrangler on December 12, 2015, 09:22:44 AM

draw should be less than 0.1A under normal locked mode.

Not on a ZG, they were always very high, hence the need to pull the IOD fuse.

Maybe this depends on the model as my 98 loredo td was 0.15A for a few seconds after locking then dropped to 0.6A. I now have a 4.0 orvis, I'll measure that later and report back
Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: bisleywrangler on December 12, 2015, 09:27:39 AM
Sorry meant 0.06A.


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Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: Jonny Jeep on December 12, 2015, 10:56:18 AM
According to the ZG/J FSM IOD should be no more than 30mA after 3 mins. It seems surprising that battery drain should be such a problem on them.
Title: Re: Parasitic Drain on a 1997 Grand Cherokee 4.0
Post by: daggie on December 12, 2015, 05:19:08 PM
alarm siren batteries, its underneath the servo