Grand Cherokee wk2 Second Battery

[David Scott]

Second battery WK2 under front passengers seat. Not suitable for vehicles fitted with air suspension.

1. Unbolt the front passengers seat and move forward then remove access cover. This has two clips at the front and two clips at the rear.
2. You will now see three wiring harnesses two with terminal blocks and one with a small plastic case with a metal back.(Don't know what it is but I did not disconnect any plugs. I did not disconnect the seat as it has an air bag fitted and was unsure weather to remove seat wiring so I just moved the seat forward and backwards while fitting the battery and electronics.)
3. The wiring harness in the floor well just unclip and place them on the carpet. Inside the plastic well also has a plastic insert that can be removed leaving the well vacant.
4. Now (be brave I know it is a new car) if you view the carpeted cover and the plastic well you will notice there is a lip on top of the well where the top cover fits over this lip. I cut the inside of the plastic well all the way around leaving the lip still there so the cover will still fit.
5. I fitted a 100amp hour GSM battery that I had taken out of my new Jayco van as I had fitted a 200amp hour battery to the van. This battery was about 30mm taller than the battery fitted under the drivers seat so I had to improvise the cover as my battery protruded above the floor however it did not interfere with the seat moving forward or backwards.
6. IMPORTANT. If I was considering doing this I would measure the current battery fitted under the drivers seat and source one of similar size. (e-bay, internet)
7. If you remove the two screws at the rear side of the consul it is quite easy to feed wire from the starting battery under the carpet to the second battery. The consul will lift a couple of mm to enable this. I made up some brackets to secure the battery and there is plenty or room alongside the battery to fit the duel battery setup.
8. I ran the cable from the anderson plug at the rear into the spare wheel well through a plastic insert in the floor and fitted a rubber grommet. There is plenty of room to run cable through to the second battery via the the side panels and kick plates. No need to run underneath the vehicle.
9. I have fitted a rubber sheet larger than the well above the battery and tucked it under the floor to seal it. In the battery well there are three plastic plugs that a drain hole can be drilled. The battery in the vehicle is sealed but does have a small rubber tubing fitted to it and vented to the outside. Perhaps when sourcing your battery you might be able to find one with a similar fitting like the starting battery has.

Good luck it is not a hard task take your time.
David Scott
Photos attached.

[zzkazu]

David , I hope you work out how to post images. I assume from your description of the install that you didn't install an isolator.

[snatchemdave]

Great to hear there is a way to mount a second battery, it is one of the issues I was concerned about in my consideration of purchasing the car. Would love to see some photos if possible.

[mlenser]

Originally Posted by David Scott

I fitted a 100amp hour GSM battery that I had taken out of my new Jayco van as I had fitted a 200amp hour battery to the van. This battery was about 30mm taller than the battery fitted under the drivers seat

Hi David,
Any idea what the dimensions of the battery you fitted was? What did you use to charge the second battery? DC-DC charger or relay?

[David Scott]

I had a 100amp hour deep cycle AGM battery that was in my new Jayco van that I replaced with a 200amp hour battery. The battery was about 320mm in length about 179mm wide and 220 mm in height. Fitted straight in except it was about 30mm higher and the lid required the 4 legs extended and the surrounding carpet built up. There was still enough room under the seat. Last night after researching deep cycle agm batteries I realized that they can be laid on the side as they do not leak and have a valve fitted if there is a build up of pressure but still do not leak any fluid. They can be fitted in a vehicle or caravan without venting. With this in mind I removed the battery made a template to the size of the side of the battery and placed it in the tub. The front corner of the tub (metal) required to be squared off. I cut the corner out and made up a new corner and screwed it in and sealed it up with black mastic. Then painted it black to match the underneath of the vehicle. Fitted the battery back in and the top now fits level as original. There is a Full River 70 amp deep cycle on ebay that is about 350 in length similar width and only about 170 in height. I thought about that one but the tub would have to be squared up to fit the extra length. You Choice I have 100 amp hour the other is only 70. I did make up a battery clamp and used a standard duel battery set up. I am thinking about a 12volt to 12volt charger down the track.
David Scott

[zzkazu]

David, I should take delivery of my car next Wednesday. Would be interested in how you installed the isolator and circuit breaker. I assume they went in battery box housed in a custom setup of some kind. I wont be installing duel batteries in the car but need the setup to isolate a 4WD battery that will be connected via Anderson plug.

Any information on how it was secured in the car would be appreciated.

[David Scott]

Hi there
I still can't work out how to post pictures. I get the icon of the thumbnail but when I move it to the post it is in writing no picture. When I do I will post numerous pictures of my mods.
David Scott