New DEF Issue and Questions

[FlaBucki]

Rolling down I95 last week through South Carolina in my 2014 IS I received a warning message that my DEF was contaminated and needed drained and filled by an authorized workshop ASAP. We determined the closest servicing dealer was in Charleston so we diverted after calling ahead. After running tests for three hours and upgrading software in the diagnostics and resetting the diagnostics, they sent me on my way after telling me they should have done a 60 mile road test diagnostic but if could wait until I got home if I preferred. We drove home without further messages.

Just picked it up today from my local dealer who essentially said they did the long road test and could not find anything wrong.

Anyone have any similar experience? I have that creeping feeling that partway through our next road trip that message and "countdown" to no start will start again. According to the two techs I spoke with at both dealers, the DEF systems on the Sprinters are sensitive and there have been problems with "false" readings. In the end, neither dealer drained and filled or even added DEF fluid to my rig.

They both also said I should only use Mercedes DEF because others do not have high enough "urea" content. I told them I had not heard or read such advice. I later checked my OM which only says to use the ISO standard they state. I have only added Blue DEF brand (which meets the ISO standard) since I have been on owner, which others have stated on other posts is available at many retailers for about $12 for a 2.5 gal jug.

One other irritation - the first dealer said all was covered on warranty. My local dealer, who I instructed was to contact the first servicer and pick up from where they left off, charged me a one hour diagnostic fee of $149. The service manager was not there so we will have further words about that tactic on Monday. Is a diagnostic fee warranted for an issue that should be covered by warranty?

Lastly, I have Service B upcoming in about 1,000 miles. Can anyone confirm that Service B includes a DEF drain and fill? Even at $5 a gallon, I would rather not top it off now if it is just going to be drained out soon.

[Protagonist]

Originally Posted by FlaBucki

They both also said I should only use Mercedes DEF because others do not have high enough "urea" content. I told them I had not heard or read such advice. I later checked my OM which only says to use the ISO standard they state. I have only added Blue DEF brand (which meets the ISO standard) since I have been on owner, which others have stated on other posts is available at many retailers for about $12 for a 2.5 gal jug.

The ISO standard is identical worldwide, including in Germany where Mercedes DEF is made. The only difference is Mercedes DEF is imported and comes in 1-liter containers with a special no-spill spout. And costs about eight times as much as domestic product. From DiscoverDEF.com:

The production, handling and transportation of Diesel Exhaust Fluid (DEF) are governed by the ISO 22241 standard. The standard covers five main points:

1 - Urea concentration: DEF must have a urea concentration of 32.5% by weight. This concentration was selected because it is has the lowest freezing temperature, 12°F (-11°C).
2 - Contamination: Contaminated fluid can damage SCR injectors and catalysts, resulting in system malfunction or failure. Therefore, the maximum level of impurities permitted in DEF, such as calcium and various metals such as iron, copper, zinc and aluminum, are clearly specified. There limits are set very low. For example, a spoon of table salt in a DEF tote would push the sodium content far above the ISO 22241 limit of 0.5 ppm.
3 - Quality: ISO 22241 excludes the use of urea granules used as fertilizer in agriculture, and requires water purified by distillation or de-ionization.
4 - Materials: Only certain materials are permitted for the storage and handling of DEF. DEF is corrosive to many materials, including carbon steel, copper and aluminum, which cannot be used. The main risk of using incorrect materials with DEF is that the DEF will be contaminated by the material, resulting in damage or failure of the SCR system on your truck.
5 - Handling guidelines: Guidelines require manufacturers to follow clear procedures for the manufacture and distribution of DEF, ensuring that the product you use meets the the requirements of vehicle manufacturers.

Is a diagnostic fee warranted for an issue that should be covered by warranty?

Diagnostic fees are never covered under warranty. However, if the diagnostic turns up a problem covered under warranty, then the repair would be covered. All you would pay is the diagnostic fee. And the fluid, if any was needed. DEF is a "consumable" and so new DEF is not covered under warranty either, just like new diesel fuel wouldn't be covered if you had a fuel tank problem.

[lewster]

I've had several DEF issues with my '11 2500 van. The first was the countdown clock coming on and activating after I had just filled the DEF tank with Mercedes' Ad Blue. That was corrected under warranty by an ECU re-flash.

Next was the countdown clock coming on at 9 and staying there, even after several more starts. I filled the tank as soon as I found an auto parts store with the right DEF (which took less than a gallon) and the light eventually went out in a day or 2. It came back on a few days later and I went back to Mercedes. This time, it was a bad sensor, which was replaced.....also under warranty.

Then the DEF light came on and as I was near the dealer, pulled in for a quick diagnostic. Seems that the DEF heater was malfunctioning and had to be replaced......out of warranty by now.

The most recent (and potentially most expensive) episode was the DEF pump. After the DEF light came on the day after an oil and filter change (I don't wait for the service computer, but have the service done at 5000 mile intervals, per the rec. of the Sprinter tech at Mercedes due to my high mileage use) it went back again, and the active code pointed to the pump. After removal and testing, the pump appeared normal but the tech was going to replace it as a prophylactic measure, as I was headed from FL to OR in a few days.......that was until he found out the price of the DEF pump......Almost $700!

At this point, he ran the pump thru a prescribed battery of tests with special equipment and cleaned any part that was accessible and put the pump back in. The tech told me that due to the strict Federal emission standards, it doesn't take more than a blip of a sensor to throw a code that illuminates an idiot light on the dash.

The DEF system has indeed been the only major PIA with this van, but there is no way around it.....yet!!!! I'm presently at 117,000 miles