Interesting thing about my Jeep Meridian's DEF level I learnt recently

Since filling the DEF to 100% last time, I have driven the SUV back to Hyderabad from Bangalore and also used the car here every day but the DEF level displayed is still 100%.

BHPian applegrew recently shared this with other enthusiasts.

In 2nd week of April, I completed a nice road trip from Hyderabad to Coorg via Bangalore. The trip went without a hitch except when I was back in Bangalore from Coorg the DEF warning came up. The DEF level was 50% at that time.

Since I was scheduled to leave for Hyderabad the next day hence I bought DEF cans from a nearby Shell fuel station (Recommended AdBlue brands for BS6 Diesel cars). I bought two 5L cans. The Shell personnel emptied out the first can and while pouring the 2nd can it spilled out a little. The 2nd can still have around 25% DEF left in it.

The issue is since filling the DEF to 100% last time, I have driven back to Hyderabad from Bangalore and drove the car here every day but still, the car shows 100% DEF level!

At the start of March, the service centre had last refilled DEF to 100%. I painstakingly jotted down every distance travelled by the car from the Jeep Life app from then till today and cross-checked that against Google Maps Timeline data.

The 50% warning came after driving for 2112km. So that means for every 42.24km travel 1% DEF consumption should be shown. I understand that the car might not show consumption of every 1%. After refilling to 100% last time, the car has travelled 971km. That means 23% DEF should have been consumed by now. However, the car still shows 100% DEF! I remember the DEF level in the car gradually went to 50% not directly to 50% from 100%.

I am very apprehensive about the reading in my car, since in a few days I will be going on another long road trip.

Update: Issue resolved

We have a long trip coming up shortly, so was growing apprehensive. Yesterday I finally bit the bullet and took it to the service centre. They mentioned that probably the sensor is not able to work correctly with the given DEF but they have not come across such an issue before. OBD checks revealed no malfunctions. Their recommendation was to drain the current DEF and refill with the recommended one.

The work involves removing a wheel to access the DEF tank. The DEF tank is behind the driver-side rear wheel and has a metal protective cover bolted around it. So all those had to be unbolted. After taking out the tank they drained it and the connecting pipe. Even after emptying out, the gauge was still showing 100%. However, after filling in 5L of the Velvex DEF the gauge was updated to show 50%. As the tank was being filled more, I could see the gauge move up in real-time all the way to 100%. After driving home the gauge shows less than 100% now.

So one thing to note is that even when the tank has 13L capacity, the gauge shows 100% at 10L. Let's do some math. Previously the service centre had filled just upto 10L. I am sure about that now, since at that time too the gauge dipped below 100% the very next day. So it took 2112km of travel to consume 5L of DEF which is 424.4km per L of DEF. So for 971km it must have used around 2.3L of DEF. In reality, the consumption would have been less than that since the 2112km part including driving on Coorg hills. At Shell, they had filled over the brim so that means the car still had 10.7L of DEF left in it. Since the car drove well so I think there was no problem at all to begin with. I overreacted and the service centre cashed in (knowingly or due to ignorance). I just had to wait a little longer.

Overall this gain in knowledge that the gauge considers 10L as 100% cost me around 7k (of which around 1k is the cost of 10L Velvex DEF). Hope this helps other confused souls.

Here's what BHPian Omkar had to say about the matter:

Glad that the issue was resolved. Jeep is extremely particular with the brand of DEF being used in their cars.

Reminds me of the issue Axe77 had with his Jeep Meridian where a different brand DEF was filled and the car refused to start - Related Thread

Here's what BHPian careind had to say about the matter:

Thanks for sharing this nugget. I think this should hold good for the other brands as well. We have to be aware of when it reaches 100% as against the total volume of the DEF tank.

Here's what BHPian sameerpatel90 had to say about the matter:

Good to hear this, the repair job didn't cost you a big sum apart from the DEF.

• What I recommend to all the BSVI automobile owners is that when you purchase DEF, it is good to have 5L cans purchased rather than 10L ones. Partially used cans when exposed to the environment may start forming into crystals and may cause blocking of DEF lines, pumps and injectors subsequently affecting the DPF unit as well.
• Always refill a 5L can only after it is below 50% this will prevent the user from overfilling (like it is usually done with fuel) and carrying a spare can for longer distances shall keep you out of the anxiety when it is low.
• There are many companies manufacturing DEF but IMHO, always use the company-recommended AdBlue as they vary in concentrations of UREA.

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