I am having an issue where my ECO mode rarely engages. It used to work all the time. Recently I have been getting a low battery warning and even a "shutting down" message on the radio display as I start the car. Once started it is fine. I took it to Jag and they tested it all out and say the battery was low, but tests out fine. Charging system is fine as well. I drive it almost every day 20 miles to and from the metro. If nothing is wrong with the charging system but the battery is still low, not sure what to do. I have debated just buying a new battery anyway (both of them) and see if that resolves the issue. It seems like on warm days the ECO works much better. I had one thing a phone charger plugged in but have since unplugged it to see if that was it but there is no change.

 

JagGate, to me it sounds like your EcoMode battery is starting to go and not have a lot of capacity left in it. I would start with the one battery (can change both if it makes you feel better) and then see what you have.

The other thing you may want to try is stepping on the brakes harder when at a stop. Members have found that the Eco system is looking at how much brake pressure is being applied and if you apply just barely enough to keep the car still, the EcoMode will not kick in. Where, if you step on the brake harder, this will cause it to engage as soon as it can.

 

I agree with all that Thermo suggested and would add that I have had a similar experience with my '13 XJ.

A couple other observations from my POV (and I would note I have only had my XJ for a couple months now....)

As the weather warms - I believe the increase in AC demand may also influence a reduction in ECO shut off? It's already in the 90's where I am and it seems to shut off less at this point than it did during cooler days just a few weeks back.

In addition - I now have a CTEK battery tender set-up in the garage and I find that after I have had the car hooked up to the tender for a day or two the ECO shut off is quicker to engage (thus supporting the battery correlation).

 

Eco mode is also affected by the A/C fan speed. If you're stopped with the A/C set to AUTO and ECO mode doesn't engage, manually reduce the fan speed until ECO mode kicks in and shuts off the engine. The engine will restart when the cabin gets warmer and calls for A/C.

I agree with Ceckman's observations that (1) increased A/C demand causes ECO mode to engage less frequently, and (2) ECO mode is quicker to kick in with a fully-charged auxiliary battery. I also have a CTEK on my XJ.

 

Are you guys hooking up the battery tender to the main or auxiliary battery? I did put a battery tender on for a few days and it seemed to make the low battery message come on even more often. It was doing no good at all so I removed it. I was connecting it to the main battery.

I have gone as far as shutting everything down in the car. Climate control off, radio off and entire display off without it working.

Also I did press the brake harder with no improvement.

When ECO is working, it works great. Sometimes annoying actually.

Also another thing on functionality of the ECO system. The car seems to know when I get home and park in my garage. Instead of just shutting off the engine, when I come to a stop in my garage the car entirely shuts off and not just ECO mode (transmission shifter retracts). Is this a "feature"?

Since the battery is out of warranty and is coming up on 4 years old anyway, I may just replace both of them with new ones. Probably DieHard. Is there an order or replacement or does it not matter? One at a time I assume?

 

I have my CTEK connected to the main (large) battery terminals.

I have experienced what you describe also relative the "total shut down" (meaning that the vehicle "acts" like you have hit the "off" button - when you have not). Everything goes off and the car moves itself into park and the transmission "puck" retracts. This has happened a couple times immediately after having filled my car with fuel and I am pulling out of the station - and also a couple times when pulling in my garage.

In addition, also oddly just after a fuel fill up, I have had "fault alerts" come up on the dash to note an "ECO System Fault" and the amber light indicates ECO Off appears. When that has happened I have turned off the vehicle and restarted and it has reset.


I am confident "this is not a feature" and believe it is a "fault" in the electronics.

My car is still within warranty- and I plan to address this at the next service visit in a few weeks.

As previously indicated - I am also still getting used to the ECO functionality - and find it a little annoying (especially with the gremlins that are present).

 

Let me know what they say. I am under warranty for another year too so if this is an issue I'll have it addressed. I meant to ask them about it at a recent service but they took an hour longer than they said and I just wanted to get out of there.