Our 2017 Sprinter died on us (and what we did)

[wanderers]

Originally Posted by BrianW

Yours is the third Sprinter horror story I heard this summer in the North Country. En route to Alaska this summer I met a guy in the Dawson Creek Walmart lot in June who had an issue with his Sprinter and had to backtrack to a Sprinter dealer somewhere many hours away, losing three days off his trip. He also told us of another owner of a nearly new 4x4 Sprinter that was at the dealer for many days waiting for a new transmission to be shipped from Germany to fix his shot one.



I love the way Sprinters look and drive, but I'd sure think 3x before buying one due to the sparse dealer network.

In 2010 we met some Germans who were stranded in Haines Junction, Yukon. They had shipped their Sprinter over from Germany. They showed it to us and it seemed to have a nice layout. They had been there a couple of weeks and had at least another week waiting for a transmission from Germany. You would think that Mercedes would stockpile some transmissions somewhere in the middle of North America (and other parts, too) so their customers wouldn't have to suffer through such long downtimes. Eight years after we met the people in Haines Junction they still have to ship replacement transmissions from Germany? That would make me leery of purchasing one, too.

[JFlo]

Originally Posted by Fitz

Here is the 150 amp fuse that Paul is talking about. (Every Sprinter owner with a house battery needs to carry a couple of these!)

Thanks Fitz! Just ordered a set.

[Fitz]

Originally Posted by Scalf77

Interested in the results of the autopsy.

-greg

Here is the fuse that failed on me. The van was fairly new and we were in Nevada with no replacement fuse to be found. Believe me, we looked, we must have tried a half a dozen auto parts stores. I found an address to use and SMB Texas overnighted a replacement to me (great customer service), and I changed the fuse in a parking lot.



As you see it here, the fuse passes a continuity test (I did it again this morning before I took this picture.) When installed, it would not pass enough voltage to allow a charge to get to the house battery. We had to come into town and stay in a KOA so we could hook up to shore power to charge the battery via the charger.

Why doesn't the fuse work when it passes a continuity test and when the internal element has obviously not melted? Got me, I'm open to your thoughts. I do know that I am aware of three similar failures and that I have had no issues since changing the original fuse.

[Scalf77]

The best I can think of from this vantage point is that I expect that is could have been a loose connection holding one side of fuse in. Overtime corrosion built that developed a resistance between the fuse and fuse holder connection. One side of the fuse appears to look a little pitted and dull, while on the other side you can see where the washer was making contact with the fuse. It is possible that cleaning the contacts would have rendered this fuse usable.

Obviously it would be even harder to comment on other failures, but improper installation could be the culprit. It is possible that it is in a difficult location, etc, that makes this a more prominent failure location.

-greg

[SteveTOaks]

Thanks to the great info in this thread, I also ordered some of these fuses. I had no idea that there were fuses next to the battery. When they arrive, I'll have to take things apart to make sure they fit. It looks like you can 't get to the fuse holder without disconnecting the wires form the positive terminal, which of course means I'll have to disconnect the ground first.


Here's what I ordered from Amazon, 2 fuses for $12.53: https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

[Sloya]

The question of not being able to tell if the fuse is working or not.
This fuse is the main source for most house batteries. SMB uses an automatic switching model to turn on charging house batteries. When this fuse blows the switch does not work to charge 5he house batteries. The easiest way to tell if the charging is working is to check your output voltage. Many SMB are equipped with an inverter with a digital display showing the current battery voltage. With the engine stopped read the voltage on the display, you can see something like 11.0 to 13.5 volts depending on battery condition. Next start your engine and read 5he voltage again, it should now be displaying in the 14.0 volts or higher. this is indicating two things, 1. The fuse is working 2. the automatic switch is working and charging the house battery.

Note: This fuse blows when too much current is being demanded. Normally you can run a microwave, coffee maker, or hydronics hot water. But you can not run all or two of these at the same time or you will blow the fuse. The hydronics got water is the biggest current draw and would recommend turning off the CB while driving and turning it on when connected to shore power. I learned these things the hardway and drove me nuts trying to figure out what was taking place to blow the fuse. I hope this helps you with understanding your systems...!

Happy Travels Everyone
Sam

[4liner]

I occasionally get the "ding, ding" sound. It happens if I try to start my 2015 Sprinter with the driver's door open. So I've learned to always shut the door first before I turn the key. If I forget and the annoying "ding, ding" sound occurs, I just pull the key out and wait a minute or so and it stops on its own.

[VtSoundman]

Add a small...small drip of loctite blue to these connections.

Drip a small amount of loctite around the top of the thread where it comes out of the bolt...it will seep down a little bit, but not affect the electrical connection.

Also, don't foget about a full reset - pull the ground connection under the footwell for sprinters. This will not clear codes, but sometimes it helps to 'reboot' the computer.

The reason fuses will pass a VOM test but not high current is carbon tracking and partial breaks - the clearing event was not enough to clear the material, but enough to cause a fracture or high impedance....

[SteveTOaks]

Here's what I ordered from Amazon, 2 fuses for $12.53: https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Turns out you only get one fuse. I was fooled because there were two fuses in the picture with the description.

[akfiredude]

Originally Posted by 1der

Thank you for sharing your well written story. Battery connections are so critical, especially these days with so many electronics.

Something about that battery cover picture is not adding up for me. The melt pattern looks like something else created it. Was it possibly modified for clearance?

Re: checking fuses - an ohm meter will tell right away if a fuse is good or bad. On the other hand, if it is a resting circuit breaker type, it may be weak under load but still show continuity at rest.

Glad you are back rolling. Your description of “Checking” multitimes a day is so accurate! Confidence in our rigs is so important. When it is shaken, twice! it takes a bit to get it back!

Thanks Ray and yes it is great to have that problem solved without having to get towed or find a long off dealer. It's been nearly 3000 miles and no further problems.

I'm not sure what you see with the burn/melt picture that looks like it was modified. The hole in the red plastic cover is for the positive terminal and it has some mild melting around the edges of this hole from where the connection was arcing. Nothing out of the ordinary and nothing was modified.

Time and problem free distance has restored our confidence again!