REPLACING THE HORN ON AN AIRSTREAM INTERSTATE

Our 2007 Airstream Interstate came with an OEM Mercedes Sprinter horn, which unfortunately wasn't optimal for the vehicle in our opinion and in the opinion of numerous other Sprinter and Interstate owners.

Video embedded above (may not display on some mobile devices):  The joke is oft made, but there's some truth to it.  The German Sprinter horn really does sound like the American Road Runner cartoon character, the Warner Brothers classic.

Image courtesy of Wikipedia.

 An Air Forums user recently commenced a thread inquiring about how to improve the Interstate's safety factor via modifying the horn to change it into something to which other drivers might respond better.  There are also Sprinter Forum-related threads on this topic, including this one titled "Horn replaced with Hella Supertones".

As I explained on the Air Forums thread, I'm in a phase of personal logistics whereby I'm doing some heavy driving in downtown Houston.  This is what IH-45 looks like at 10:00 a.m. on a Saturday morning - hell has already broken loose and it's not even noon yet!  With a large lumbering Interstate in heavy traffic, a good horn is often needed for polite communication purposes. If the horn on the vehicle doesn't correspond to what people expect to hear, it can result in other drivers becoming confused or ignoring the message.  

No oversized vehicle gets through stuff like this without a bit of negotiation.  An occasional beep may be part of that. Let me through!!
:-)  

To boldly go where no RV has gone before:  I spent the morning traveling with my DSLR in my lap so that I could take a few representative pics of the kind of messes one typically encounters in this urban realm.  These guys did move that far right barrel and let me through as soon as that loader delivered the pallet.  Regarding that metal plate covering the gaping hole in the right lane, I thought to myself, "Hmmm... I hope these guys spec'd that thing correctly.  I guess we'll find out..." 
:-)

My husband did the research on which horn to use as the replacement, and chose this:

Hella Super Tone B133 horn set.  

The following photo series documents how the replacement was achieved.  If you attempt this as a DIY project, mind that you will be working with the vehicle's electrical system, and if you screw it up, the result could be bad.  See also our BIG FAT DISCLAIMER.

Not my husband's typical garage work attire, but he did this little project just prior to leaving for backshift. Such is the life of the non-retired. 

On the T1N Sprinter, the horn is easily accessed by removing the front grill.  

It's that nondescript little round thing in front of the radiator. 

Here is how that original horn appeared looking down from above (photo center).  The green plug thing to the left was attached to it.  

Here it is removed, compared to one of the new Hella pair.  

The main time sink and complexity with this project involved the creation of a second mounting bracket, as the T1N Sprinter only had one to start with, because it only had the single horn unit.  The come-with Hella bracket had to be modified to fit the available space. 

That other bracket, as finished, can be seen at photo left.  The two horn units were attached side by side with the new bracket mounted near the radiator base. 

Another shot of that attachment.  

My husband did the research on how to wire this properly (the horn pair is wired in parallel).  Something about verifying a Sprinter relay and not needing to add another relay because one was already there.

Horn wire feeding from the Sprinter, green connector snipped off. 

Attempted soldering action shot. 

And shrink-wrapping.  

And spray-painted, because the crimson showing through the front end looked tacky.  Normally I would spray paint parts prior to installing them, but we did the installation Friday night and I needed to use the Interstate Saturday morning to take our daughter to a class downtown.  So our order of operations got reversed - I spray painted them after returning home on Saturday. 

I did a better in situ spray painting job than Airstream had done with the Interstate's garnet trim paint.  Good grief, there is sloppy workmanship everywhere I look in this rig.  

And here is the money shot, job all done.  Ta da!  No more in-your-face lipstick color.  

On my maiden horn-voyage into downtown Houston, I had to issue one warning tap to a scatterbrained freeway driver who felt strangely obligated to try to broad-side me.  These horns, with dual tones, sound much more American style than the single-toned original Sprinter unit.  They are not overly loud or obnoxious - just typical, as in, what you'd expect from a large motor vehicle.  We actually took video of the before-and-after horn sounds, but the iPhone did not capture the comparison well so I won't bother to upload it - the new one is louder, but the iPhone microphone was saturated by both, so the representation is not accurate.

Oh, and just in case you were wondering, we have no imminent plans to install an air horn in our Interstate, an option that some folks contemplated on Air Forums.  We were shooting for a normal-sounding horn, not something that would scare people half to death.  Although I must admit, when I saw this YouTube video below, which illustrates the result after one owner installed an air horn in his Sprinter, I had to giggle at the absurdity of it.  Be sure to turn the volume down on your device before watching.  BAAA-AAARP!!!!

Link: https://www.youtube.com/watch?v=ouaJdrUQPvA

Embed:

I'll close with a short photo series from today's urban journey because why not??  Because pretty pictures are always cool and because Houston is now in its most beautiful season.

The aforesaid newly-horned Interstate nestled in the urban landscape beneath a shady live oak.  Where possible when parking in urban locations, Interstate owners should try to back into parking spaces (we don't have our back-up camera installed yet, so I did not).  As the day progresses, parking areas infill, sometimes to unworkable levels of density.  It can become quite a challenge to back out again.  

Houston is known for its spectacular live oaks.  Hermann Park, an approximately 500 acre recreational area near the city center.  

Entering the McGovern Centennial Gardens in Hermann Park.

View from atop The Mount, an earthen sculptural feature with a spiral access walk.  

Houston blooming.  

And growing. 

Confucius say, go ahead and replace your Airstream Interstate horn.  You won't regret it.  

Still in Hermann Park with the Texas Medical Center in the background, the largest medical complex in the world.