Jeep Garage  - Jeep Forum

Jeep Garage - Jeep Forum (http://www.jeepgarage.org/forums.php)
-   2014+ Cherokee-KL (http://www.jeepgarage.org/f216/)
-   -   Parasitic battery drains (http://www.jeepgarage.org/f216/parasitic-battery-drains-69710.html)

grandriver125 12-28-2013 11:17 PM

Parasitic battery drains
 
We had this problem with our Town & Country. They eventually traced it to the 3rd row power seat. The module was not functioning properly and it was allowing an every so small drain. It wasn't until the vehicle sat unused for just over a week that it would no longer start. Under normal driving it was not noticeable.

I may have the problem in our Cherokee. Battery seems to charge to over 12.57 and then in a few hours it is down to 12.25 and declining.

Anyone else have this problem and was the dealer able to identify the source. They have to go through a process of checking the current flow at the battery and if it is visible then fuse after fuse to identify the circuit. With so many electrical items on the Limited it could be just about anywhere.

Any advice? Monday I'm having lunch with my dealer salesperson so I think I'll take it in and they can observe the decline while we at the restaurant. I'm hoping it is not something that they have to search and search and search for as we plan to depart for FLA in a wee.

GR

bill_de 12-28-2013 11:25 PM

Re: Parasitic battery drains
 
There are some electronics always on in your Jeep. They will probably pull the surface charge down pretty quickly. If it doesn't go below 12v, there is probably nothing at all wrong. If you hadn't had a problem with a previous vehicle, you wouldn't be looking for one now.

Of course I can't be sure. But for your sake, I hope I'm right. ;)

grandriver125 12-29-2013 10:06 AM

Re: Parasitic battery drains
 
Bill, I responded last night but the post must be in cyberspace.

We've had issues like this up to our eyeballs - with our five motorhomes. They all came with house battery kill switches but only one came with a chassis battery kill switch as well (two of them had two chassis batteries). For the current unit I installed a kill switch on the negative post and in the summer when not in use kill the flow of power.

We constantly monitor the voltage because there are just loads of things that seemed to steal power - such s the Allison transmission memory that stored a learning mode (sound familiar).

Between 11 and 12 last evening voltage was down to 12.25. This morning it was 12.15. Frankly, in all the monitoring of our MHs I never observed this kind of drop so quickly. Over a few weeks but not 6 hours.

When I went out to the garage this morning the lights went on - in my head. Check the Town & Country - it is outside the garage. So I did. IDENTICAL 12.15 volts. Now that has me wondering about my multimeter (checked the 9V battery -0k). BUT, we pulled the 2 house batteries and the single chassis battery out of our motorhome in late October. They are stored in the basement on 2 x 4s and I made sure they were fully charged before we headed south. They are all still reading 12.6+ volts (obviously no drain as not connected to anything).

Now I am puzzled or maybe I've just never encountered this situation and it is normal - but everything I read tells me it is not normal, as 12.15 means it is less than 50% charged. The T&C will be sitting for almost 60 days and I will disconnect the negative terminal. We also did this with our Flex when it was left unused as it had lots of drains and the manual warned about them and strongly suggested disconnecting. But it never dropped so much in a day. The T&C has not been run for 33 hours and yet it had the same voltage and it is outside vs inside for the Cherokee. So, not sure what to conclude.

I've asked my son who lives nearby to check the voltage on their Caravan and Verona which have not been run for almost 2 days.

Thanks

GR

Oh, info centre says voltage 11.8 to 12.

Desert Hiker 12-29-2013 11:19 AM

Re: Parasitic battery drains
 
I'm not a battery engineer, but a wild hair thought: could it be that the voltage drop is related to the ambient/internal temperature drop of the battery: higher internal temp after driving (engine compartment heat gain + charging heat gain), and then dropping to ambient (coooooold!!!) after sitting for a while? Of course output (and thus possibly even low drain voltage) of batteries drops as temperature drops. "Internal resistance" of batteries increases as temperature drops, thus reducing output capacity. However, this may only show up as increased voltage drop under load (starting) and not voltage drop in an low drain (vehicle off) situation - not sure. Your motor home batteries are in your warm and comfy basement. As a test, place them outside and test their voltage drops in a few hours.

BTW, we had a new car years ago that had a mal-adjusted microswitch in the console. It was a challenge to find because it was not evident that the light was on sometimes when the lid was closed. Of course it was "off" when the dealer was trying to diagnose it. I finally found it - fix was easy.

Desert Hiker


Quote:

Originally Posted by grandriver125 (Post 951580)
Bill, I responded last night but the post must be in cyberspace.

We've had issues like this up to our eyeballs - with our five motorhomes. They all came with house battery kill switches but only one came with a chassis battery kill switch as well (two of them had two chassis batteries). For the current unit I installed a kill switch on the negative post and in the summer when not in use kill the flow of power.

We constantly monitor the voltage because there are just loads of things that seemed to steal power - such s the Allison transmission memory that stored a learning mode (sound familiar).

Between 11 and 12 last evening voltage was down to 12.25. This morning it was 12.15. Frankly, in all the monitoring of our MHs I never observed this kind of drop so quickly. Over a few weeks but not 6 hours.

When I went out to the garage this morning the lights went on - in my head. Check the Town & Country - it is outside the garage. So I did. IDENTICAL 12.15 volts. Now that has me wondering about my multimeter (checked the 9V battery -0k). BUT, we pulled the 2 house batteries and the single chassis battery out of our motorhome in late October. They are stored in the basement on 2 x 4s and I made sure they were fully charged before we headed south. They are all still reading 12.6+ volts (obviously no drain as not connected to anything).

Now I am puzzled or maybe I've just never encountered this situation and it is normal - but everything I read tells me it is not normal, as 12.15 means it is less than 50% charged. The T&C will be sitting for almost 60 days and I will disconnect the negative terminal. We also did this with our Flex when it was left unused as it had lots of drains and the manual warned about them and strongly suggested disconnecting. But it never dropped so much in a day. The T&C has not been run for 33 hours and yet it had the same voltage and it is outside vs inside for the Cherokee. So, not sure what to conclude.

I've asked my son who lives nearby to check the voltage on their Caravan and Verona which have not been run for almost 2 days.

Thanks

GR

Oh, info centre says voltage 11.8 to 12.


grandriver125 12-29-2013 11:59 AM

Re: Parasitic battery drains
 
DH, that is the aspect I don't know - how the voltage drops with temperature. Sure know how tire pressures drop. In the past we usually took our motorhomes to Florida. I always joked that the easiest way to winterize is drive it to Florida. The past two years we've stored them and removed the batteries.

Temperature in the garage is 43 deg F and outside is about 40 deg F now but was certainly lower overnight.

I've asked my son to check his two vehicles and that will give me a benchmark. He just called and the Caravan was 12.52. He had to use the other car so it was not checked.

GR

grandriver125 12-29-2013 12:47 PM

Re: Parasitic battery drains
 
I decided that enough was enough. The T&C is down to 12.1V now.

I have removed the leads from the Cherokee battery and wrapped them to make sure no touching accidents. I have a Smart Charger on will leave it on until it goes to float phase. (It did not indicate any faults at the start of charging which is a good sign I guess.) Then, I'm going to monitor it hourly. Only problem is that it will have a surface charge. But, if it loses nothing after 6 hours I'll connect it up to the Jeep again. If the voltage then drops again and keeps declining in it goes to the dealer.

Going to do the same thing with the T&C.

grandriver125 12-29-2013 11:43 PM

Re: Parasitic battery drains
 
Results of this exercise were interesting and you may wish to note what has happened in case you find yourself in the same boat.

After the battery was fully charged by the Smart Charger I left it disconnected for a couple of hours. No decline. Then, I connected the positive and negative cables. It has dropped very little and is still at 12.9 six hours later.

What happened? My guess - and we should have some Jeep tech guys here who can indicate if they think this is plausible. Something may have been "on" and draining power - like the USB and SD card slots since I had them in and out so many times trying to get the right SD card and USB drive working. When I disconnected the battery whatever was draining the power stopped operating. When I reconnected, whatever was draining the power did not restart (yet). IS THAT POSSIBLE?

My T&C is now down to 12.1 and I'm tempted to disconnect the battery and reconnect it.

grandriver125 12-30-2013 09:42 AM

Re: Parasitic battery drains
 
This morning voltage was still just where it was last night 9 hours earlier, so I'm feeling much better. BUT will the problem crop up again. Going to monitor very closely.

Now to address the T&C. It got even cooler (people in FLA would say damn cold) overnight. The T&C is outside and I hope it will start this morning. It is going in for oil change and filter.

grandriver125 12-30-2013 11:52 AM

Re: Parasitic battery drains
 
Problem should be solved Thursday when they will do 3 updates.

The first will be for the radio which does not always shut off when the ignition is turned off. That is what happened to ours and when I disconnected the battery it shut off the radio. Apparently the fix will shut everything off after a set period following the ignition being turned off.

Second is for the transmission to correct hard shifts from 2 to 3 and one other.

The 3rd is for a park assist problem. In certain conditions it may indicate that there is adequate room to park when that may not be the case.

GR

bill_de 12-30-2013 12:00 PM

Re: Parasitic battery drains
 
The fix for the first might be you setting the delay time in the evic.


---

Desert Hiker 12-30-2013 12:02 PM

Re: Parasitic battery drains
 
Quote:

Originally Posted by grandriver125 (Post 951939)
........................................
After the battery was fully charged by the Smart Charger I left it disconnected for a couple of hours. No decline. Then, I connected the positive and negative cables. It has dropped very little and is still at 12.9 six hours later.
......................
Something may have been "on" and draining power - like the USB and SD card slots since I had them in and out so many times trying to get the right SD card and USB drive working.
.........................

A thought (USB + SD card drain), but doubtful. A peak condition car cranking battery (75 to 100 amp-hour capacity) should be able to support the standby current drain of USB + SD card (< 200 milliamps each) for MANY hours without significant loss of voltage. Likely something else was "on", went "off" when you disconnected the cables, and stayed "off" when reconnecting. Steering wheel heater? Seat heater? Any lights? An Amprobe w/ DC current capability would be just the ticket to see what current is flowing through the battery cables under your various scenarios, but wiring harnesses make it a PITA to use Amprobe clamps at the branch circuit level.

Good Luck!!!

Desert Hiker

grandriver125 12-30-2013 12:12 PM

Re: Parasitic battery drains
 
Quote:

Originally Posted by bill_de (Post 952134)
The fix for the first might be you setting the delay time in the evic.


---

It was set for ten minutes.

An interesting aspect of this radio is that there is NO off switch. You can blank the screen but you cannot turn it off. Only way to turn it off is the ignition switch.

Apparently various functions could turn other function on as well to compound the problem.

GR


All times are GMT -5. The time now is 11:07 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community