[cmtaz]

Maybe try some Velcro wraps?

Thanks, Should have thought of that. Being a networking IT guy, I use Velcro cable wraps for everything.

 

[Dasher57]

Thanks, Should have thought of that. Being a networking IT guy, I use Velcro cable wraps for everything.

I just stick it between the battery and fuse box, it’s out of the way and doesn’t move anywhere.

 

[UN4GTBL]

I have my battery tender plug and my block heater plug come out down behind my driver's side tow hook, and it can be looped around the hook and stuffed back in there when I'm not using them. They are easy to get at when I do need them, and I don't need to open the hood (as that would be annoying!)

 

[1stWkMyDoorHandleCameOff]

Hi all, I posted recently -but possibly not in THIS thread-- about my '15 Trailhawk needing 30-45 minutes of driving for ESS to function after sitting in my driveway for a week or two.

I just want to see if I understand this and ask a few questions.

1. So on a two battery system, the (larger) under-hood AGM battery is the battery that starts the engine, and the smaller (often hidden) smaller battery powers the electronics while the engine is stopped. Correct?

2. ESS is a system --which I like because I stop frequently on off-road trip and enjoy the silence while I'm looking at a map of viewing wildlife w/ binoculars-- and in a two battery system what do you call the two batteries? Seems to me it's a Start battery and an accessory battery. I wouldn't call either of them an ESS battery as it takes the entire system and both batteries to perform Start/Stop.

3. In a two battery ESS system, the smaller (Accessory) battery is powering the electronics and the larger (Starting) battery is waiting to start the engine when the pedal is released or say for example A/C is required. Correct?

4. Does the ESS system isolate the main battery from the car so that only the Acc battery is discharging? Is there a relay somewhere that opens the circuit? Otherwise wouldn't both batteries --which are just two batteries in parallel-- discharge equally?

5. Once the engine restarts, the alternator charges both batteries as needed.

On a single battery system like mine, the single battery powers everything, and the ESS (or IBS system) simply insures the battery doesn't drain too far and then restarts the engine. Correct?

In summary, I guess my biggest question is does a two-battery ESS system actually isolate the starting battery while ESS is active and the engine is stopped? If so, how and where is this function performed?

Thanks, for all your info.

As an aside, I just put my M/C trickle charger on my ONLY battery and will see how my ESS performs once my trickle charger says it's maintaining the battery fully charged.

P.S. My battery was charging at 12.28v when I first hooked it up. and rose up two 12.36 in 5 minutes or so. which seems fairly positive. (Ha Ha; but not intended to be a battery joke...)

UPDATE: It only took my Battery Tender Jr. (12v, 750mA) about 12 hours to turn solid green (indicating it's maintaining a fully charged battery). At that point my battery/tender combo was reading 12.85v iiirc; kind of surprised it didn't come closer to 13.2v. But ESS works normally now as soon as the car is warmed up, provided I have my seat belt on. Going on a long trip where I'll be torturing my battery by opening and closing the rear gate and using a USB charger while camping, so I'll see how it goes.

 

[sanghill]

-

 

[Mark_]

1, NO, only 1 battery. The Grand Cherokee has 2 batteries, both under the passenger seat.
2, see #1.

He knows. He stated his has only one battery. He's just asking how 2-battery systems work.

Edit : Ok... you're off the hook

 

[sanghill]

You are too quick, my comment is now 'no comment'.

 

[cmtaz]

"As an aside, I just put my M/C trickle charger on my ONLY battery and will see how my ESS performs once my trickle charger says it's maintaining the battery fully charged."


Odds are your ESS will perform as intended once it has been trickle charged. I have / had the exact same issue. ESS is always in 'battery charging' mode, goes to Start / Stop Ready after 30 - 50 miles of driving. This is caused by my mainly driving around my retirement community (short 2 miles drives). Now (about once a week) after I see battery charging message, I toss it on the battery tender and by the next day it works as it should.

 

[Tico007]

When I first picked up the 2019 limited, the battery was pretty weak. A lot of the problems described here. Likely because it had been sitting on the lot for some time. I suspect that it was sitting because of the initial flat spots in the tires. Charged for a couple of days and it’s been good ever since. No more errors. I put the charger back on the other day to check on it, see if it’s holding a charge. Took a few hours and it was back to a full charge. AGM batteries definitely require more time with the charger I’m using than a regular battery. I’ve been through many charger brands over the years. My favorite is the batteryminder brand with desulfur. Some type of pulse that descales. Does that really work? I don’t know. But I have not replaced a battery on any vehicle for 5 years. I have one ACDelco battery in the family with a 2012 manufacturing stamp. It’s still in service. It’s currently maintaining an Escalade sleeping in the garage. It’s been in used constantly. Has not failed. The device charges any type of battery. What it lacks in fancy displays it gives back in fully functional batteries. If anybody is interested, this is the 1510 I use. Comes with the attachments if you want to permanently fix. This is the lowest amps I would use on an AGM battery.
BatteryMINDer 1510: 12 Volt-1.5 Amp Battery Charger, Battery Maintainer, and Battery Desulfator – Designed for Cars, Trucks, Motorcycles, ATV, Boats, RV https://a.co/d/28xDZC1

 

[Dasher57]

When I first picked up the 2019 limited, the battery was pretty weak. A lot of the problems described here. Likely because it had been sitting on the lot for some time. I suspect that it was sitting because of the initial flat spots in the tires. Charged for a couple of days and it’s been good ever since. No more errors. I put the charger back on the other day to check on it, see if it’s holding a charge. Took a few hours and it was back to a full charge. AGM batteries definitely require more time with the charger I’m using than a regular battery. I’ve been through many charger brands over the years. My favorite is the batteryminder brand with desulfur. Some type of pulse that descales. Does that really work? I don’t know. But I have not replaced a battery on any vehicle for 5 years. I have one ACDelco battery in the family with a 2012 manufacturing stamp. It’s still in service. It’s currently maintaining an Escalade sleeping in the garage. It’s been in used constantly. Has not failed. The device charges any type of battery. What it lacks in fancy displays it gives back in fully functional batteries. If anybody is interested, this is the 1510 I use. Comes with the attachments if you want to permanently fix. This is the lowest amps I would use on an AGM battery.
BatteryMINDer 1510: 12 Volt-1.5 Amp Battery Charger, Battery Maintainer, and Battery Desulfator – Designed for Cars, Trucks, Motorcycles, ATV, Boats, RV https://a.co/d/28xDZC1

This is the trickle charger I use as it’s also suppose to desulfur the battery but the battery being a sealed unit don’t know. But I never have any ESS issues and the battery is always fully charged especially if the car is going to sit for a few days.

 

[AZJeeper]

In summary, I guess my biggest question is does a two-battery ESS system actually isolate the starting battery while ESS is active and the engine is stopped? If so, how and where is this function performed?

It's not exactly straightforward. Here is a great (but dry) video that shows how the JL is wired...