parasitic power draw

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cplchris

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2006 liberty sport 3.7l 4wd automatic

long story short: my battery is drained enough to be useless every morning/whenever the jeep sits for more than about 8-10 hours.

after performing the ignition off draw test per the fsm these are the results:

parasitic draw: about 0.165 amps

on the main power distribution block in front of the battery, fuses 3 and 7 are responsible for my power draw issue (both are 50amp junction box fuses).

i could not find how to override the door ajar switch so for the interior fuse panel i would disconnect the meter, open the driver's door, pull a fuse, close the door, reconnect the meter and read the power draw.

interior fuses that indicated excessive draw:
fuse 33: SKIM module/data link connector (power draw dropped to 133mA when i pulled this fuse and no others)

Fuse 34: Body Control Module/Cluster/interior lights, hands free module/radio/cmtc/itm module and siren (power draw dropped to 6mA when i pulled this fuse and no others)

i do have an aftermarket radio installed, (have had the same one for about 4 years, with a 150watt alpine amp), since i was having issues with the stock wiring for the speakers, all the speakers have dedicated wires run to them now, i know that the amp is not causing any issue because i pulled the power fuse for it and draw stayed at 165mA.

i also disconnected the multi function switch completely and draw was unaffected.

does anybody have any pointers as to what to look for next? i plan on getting a new battery but i would like to fix the draw issue first.

thanks in advance.

edit 1: also worth noting my alternator output went from 13.7-13.9 volts to 14.3-14.6 volts since i have been having issues with the battery. the alternator is a napa rated for 136amps (166 amp peak) with a little over 3,000 miles on it.
 
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renegade 04

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Did you think of replacing the ignition switch? I know that I recommend this a lot, and it seems like more and more liberties are having the same problem.
 

Billwill

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Fuse 34 seems to be a major problem with owners having parasitic draw....this red wire spreads out to many places via lots of splices and I have been involved in lots of identical posts to this.

I presume you have the wiring diagrams for your 2006 model?

Have you completely disconnected the radio and amplifiers?

This problem has often been caused by the internal cabin lights having shorts but you need to take the wiring diagrams and physically cut off one branch at a time to see which branch is causing the power draw....leave the BCM branch for last.

In other words start by cutting the Red wire at connector C2 pin 18 on the Junction Block inside the cabin....unless you have the correct Pin Removal Tool. This eliminates a lot of possible problems such as the cargo lamps, radio and all other functions coming off Splice S311.

If that stops the current draw then you need to solder the cut wires back together and insulate with heat shrink insulation and then progress further down this line and cut off branches one by one, re-connect and continue until you have found the culprit.

If this did not stop the problem, reconnect the cut wire and turn to the other wires such as the wire coming off C1 pin 27 going to the Cluster.

There really is no other way to find the wiring branch or component that is causing this current draw than to go through this procedure....I have been there, done that and got the T Shirt many times in in my previous career and with my own 2002 Export CRD!
 

cplchris

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Did you think of replacing the ignition switch? I know that I recommend this a lot, and it seems like more and more liberties are having the same problem.

Yea i saw that you fixed your power draw by replacing the switch, i still have to check a few other systems before i start throwing parts at it. Ill be happy if the fix is that simple
 

cplchris

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Fuse 34 seems to be a major problem with owners having parasitic draw....this red wire spreads out to many places via lots of splices and I have been involved in lots of identical posts to this.

I presume you have the wiring diagrams for your 2006 model?

Have you completely disconnected the radio and amplifiers?

This problem has often been caused by the internal cabin lights having shorts but you need to take the wiring diagrams and physically cut off one branch at a time to see which branch is causing the power draw....leave the BCM branch for last.

In other words start by cutting the Red wire at connector C2 pin 18 on the Junction Block inside the cabin....unless you have the correct Pin Removal Tool. This eliminates a lot of possible problems such as the cargo lamps, radio and all other functions coming off Splice S311.

If that stops the current draw then you need to solder the cut wires back together and insulate with heat shrink insulation and then progress further down this line and cut off branches one by one, re-connect and continue until you have found the culprit.

If this did not stop the problem, reconnect the cut wire and turn to the other wires such as the wire coming off C1 pin 27 going to the Cluster.

There really is no other way to find the wiring branch or component that is causing this current draw than to go through this procedure....I have been there, done that and got the T Shirt many times in in my previous career and with my own 2002 Export CRD!

Yea i have the complete FSM, i haven't disconnected the radio, (ran out of daylight), so before i start tracing the ground the cut and test way i plan on checking the radio, ground connection beneath the rear seat, ignition switch, and amplifier wiring.

I don't believe the amp is the issue as when it was disconnected from the battery there was no change in draw.

Thanks for the help

Also, is it possible that if my battery is going bad, (load test gave me like 10.5 volts saying it was weak), that the battery could cause the bcm to constantly draw power for some reason? In other words, should i replace the battery and check for draw again?
 

cplchris

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problem seemingly solved.

the battery i had was only putting out 365CCA (napa legend 84 which i think was rated for like 880cca), so i think it had a dead cell (voltage was low as well and it wouldn't charge up to more than 12.1 volts).

replaced it with a napa 9834 legend agm and when i got home i unhooked the negative cable, put the meter in series between the post and cable (with the vehicle shut off as i normally park it) it read 165mA for about 10 minutes before everything went to sleep and it read 13mA. i'm guessing the nearly dead batter was causing some system to keep activating.

in either case i am happy to not have the draw issue any more but i will definitely keep an eye on it.

now i'm going to shop for a good agm charger
 

stevecon

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Hi - I'm resurrecting this post as opposed to starting a new one - for now anyway. I just got an '05 Liberty that suffers from this popular phenomenon. I have just under 2000mA draw on my battery that originates in JB. Fuse #3 is responsible for ~200mA of it and #34 has ~1700mA balance. Since it seems some of you have been down this path before - I thought I'd ask about your method(s). I'm an electrician (commercial / industrial - not automotive) and plan to use a "clamp-on" type ammeter wherever possible to avoid having to physically break circuits (and soldering to reconnect afterward).

I'm particularly interested in the locations in the vehicle that are accessible to clamp around wires orginating from the fuses / BCM to take these measurements. Of course, places that have been found to be popular fault locations (due to poor design, etc.) are also of interest.

I have read a lot of people talk about the ignition switch - but my key will not come out unless it is off and the radio shuts off when it is out. Unless there is another way power is still enabled through the ignition switch when the key is out - it would seem this is not the source... but troubleshooting tips for the ignition switch would be helpful.

Thanks!
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stevecon

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Found & fixed!

Thanks for the replies!

I found (by accident) that it was caused by the factory Stereo / CD Player. Ugh! I had replaced it with a JVC stereo w/ BT and USB connections before I jumped into searching for the source of the power drain.

It appears I was too impatient waiting for the BCM to time out completely. I chased ignition switch and cigar lighter related drains (to find out the multi-outlet power port I had plugged into the cigar lighter had a small power draw unless I either switched to off or unplugged completely).

All is good! Thanks again!
 

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