Relocate transmitter antenna wire DIY

canyoneer

2017 144 High Roof
Thanks 98Firebird! This worked great!

This was my first mod on my new van, which I just brought home two days ago. This write up was perfect, so nice to have all the little details, with everything highlighted. At first, after I found the antenna wire and removed it from the fabric tape, I just tried positioning it up toward the dash, just to see if that may offer a small improvement, mainly because I was shy about removing the stereo trim panel. But after testing the key fob with the wire in that position, it did not make even a small difference, I still had to practically touch the rear door with the key fob on order for it to activate the locks from the rear, and still had to be within ten feet in front for it to work.

So I begrudgingly removed the stereo trim and the trim piece to the right of that, which was actually really easy with a plastic scraper. I was a little perplexed as to what zip tie I needed to cut, but after I found the third piece of fabric tape and removed that, I could tell that the wire would be plenty long to route up through the side of the dash vent and up toward the windshield. This was also on a 2017 and that matches BrayzieSprinter's notes about the three fabric tape pieces. I was able to carefully remove one of the pieces of fabric tape and cut it into about four small strips to reuse for securing the wire up top in its new location.

I can't believe the difference. Not only does it work from at least 50 feet away, it also works from inside the house.
 

98Firebird

Active member
Haha
This is the other side of repairing cars!
Sometimes it has its good sides--like as an apprentice there was a bone rendering plant nearby.
The stink you could ignore but the rotting flesh inside truck cabins and cargo areas took some getting used to! Not allowed in the shop I used to get triple time to fix 'em and quad time on Sundays.
That stated the worst i have heard is a guy I knew who worked at the Ford main dealers in town!
A trade in Ford Cortina had little cabin heat and it stunk with the heater switched on!
Digging into the heater trunking he found it all blocked up with fully charged used condoms!
Great job for a Monday morning at 8,00 am!
Dennis
Wow! That Ford guy had a bad day! I can only imagine the rotting flesh smell either, nasty nasty stuff.

@98Firebird, was there any mention in the bulletin on what years this fix applies to? I say this because I just recently had the dash of my 2015 torn apart. There was a wire that looked like the antenna above the radio head unit in the dash under the top/center dash compartment. I didn't relocate it at the time because your write up wasn't done. However, my FOB range was terrible. I could almost never get a double click to open all the doors. After the work I did, it now works great. I replaced the head unit and speakers. I'm wondering if there wasn't some interference from some of the other factory wiring that I did disconnect/move.
I believe the document just said 906 chassis which is everything 07 and up I'll have to look. There could very well have been some interference that you took care of while you were in there.

I just got done completing this project. It took me about 20 mins to do. The antenna wire has a female connector at the end and is held by three pieces of fabric tape running along the support bar underneath the dash. There is a huge difference in range. Before re routing. I would be just over ten feet away and would have to walk closer to the vehicle to lock it or unlock it. I would also be directly behind the van trying to unlock and would have to step to the side and aim the fob to the front doors to unlock and hit 4 times to respond and ask myself why did I pay so much for a pos that can’t even unlock the doors with the oem fob . After re routing. I can unlock and lock around 30 feet away with no obstructions and from behind the rear doors. No more issues.


I do have after an aftermarket system with the mid city engineering module
But I hate carrying extra weight on my keys
Unlocking with aftermarket fob. Then using oem key to start it. Seems annoying. Personal preference

Anyways. This was done on a 2017 Mercedes sprinter
Glad it worked out for you thanks for the input/results


Thanks 98Firebird! This worked great!

This was my first mod on my new van, which I just brought home two days ago. This write up was perfect, so nice to have all the little details, with everything highlighted. At first, after I found the antenna wire and removed it from the fabric tape, I just tried positioning it up toward the dash, just to see if that may offer a small improvement, mainly because I was shy about removing the stereo trim panel. But after testing the key fob with the wire in that position, it did not make even a small difference, I still had to practically touch the rear door with the key fob on order for it to activate the locks from the rear, and still had to be within ten feet in front for it to work.

So I begrudgingly removed the stereo trim and the trim piece to the right of that, which was actually really easy with a plastic scraper. I was a little perplexed as to what zip tie I needed to cut, but after I found the third piece of fabric tape and removed that, I could tell that the wire would be plenty long to route up through the side of the dash vent and up toward the windshield. This was also on a 2017 and that matches BrayzieSprinter's notes about the three fabric tape pieces. I was able to carefully remove one of the pieces of fabric tape and cut it into about four small strips to reuse for securing the wire up top in its new location.

I can't believe the difference. Not only does it work from at least 50 feet away, it also works from inside the house.
No problem glad to help, good to hear it's working out well. Thank you for the input.
 

zither99

Active member
Man when was this repair bulletin released?!? This 906 model is in production since 2006, why only now this has been revealed?!

This mod is a must!

THANK YOU OP!!!
 

Farfrumwork

Active member
Luckily my '17 (built 12/30/17) has good FOB performance as delivered so far.

I locked the van doors from my bathroom window, about 60ft away on the 2nd floor.

I wonder if they have updated this at the factory?
 

Aqua Puttana

Poly - Thread Finder
Thanks 98Firebird! This worked great!

... This was also on a 2017 and that matches BrayzieSprinter's notes about the three fabric tape pieces. I was able to carefully remove one of the pieces of fabric tape and cut it into about four small strips to reuse for securing the wire up top in its new location.

I can't believe the difference. Not only does it work from at least 50 feet away, it also works from inside the house.

Luckily my '17 (built 12/30/17) has good FOB performance as delivered so far.

I locked the van doors from my bathroom window, about 60ft away on the 2nd floor.

I wonder if they have updated this at the factory?
:idunno:

They may still be installing them as before (engineering knows best) and only doing the modification if the customer complains.

Mercedes isn't always proactive about addressing things. No recall for the 906 Wye cable comes to mind. The replacement part was eventually redesigned, but never offered as a recall upgrade. The rear A/C leaks took litigation. Similar situations exist for other parts. Re-design for replacements and newer models, but no action to help the customer.

I am somewhat jaded though so maybe it is just me.

vic
 

98Firebird

Active member
:idunno:

They may still be installing them as before (engineering knows best) and only doing the modification if the customer complains.

Mercedes isn't always proactive about addressing things. No recall for the 906 Wye cable comes to mind. The replacement part was eventually redesigned, but never offered as a recall upgrade. The rear A/C leaks took litigation. Similar situations exist for other parts. Re-design for replacements and newer models, but no action to help the customer.

I am somewhat jaded though so maybe it is just me.

vic
I'll look the next time I have a newer van in for the takata recall and have the passenger airbag out. Wouldn't be surprised to see the exact same routing. I think you're 100% correct from what I've seen MB is not proactive at all about anything on the sprinters. I'm still a firm believer that if it's not an MB car they really aren't that concerned almost seems like the vans are a burden to them. It's amazing all the extra diagnostic help and LI documents I get for issues on the off chance I get to work on an MB car. The fused cable cracked me up the first time I did one and cut the heat shrink off to see what all was in there. Reminds me of something we MIGHT do the night before a stereo show to get a fuse installed to test the vehicle on the termlab mic, very amateurish and also makes it non serviceable. Actually sent a picture of that cable to a guy that I use to be teammates with for stereo competitions that owns his own stereo shop now and he said "who did that install? Looks like s@@t". The A/C units leaking really disappoints me also. I have a 15 year old camper and it does not leak a drop from the a/c unit when it rains. All they use when replacing the seal is a re-branded universal window seal with some notches cut in it, once again not very impressive for a multi billion dollar company.
 
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sprint2freedom

2008 NCV3 170ext
I did this modification yesterday on my 2008 using the writeup in post #1. Everything went smoothly. The directions left out a minor step: between removing the first 3 screws and the second 3 screws, you need to push up on the two tabs inside the glovebox so that the front of the box swings down. Otherwise, the second 3 screws won't be visible or accessible.

The antenna was more hidden than I expected (I could feel it but not see it, even with my head on the tool/jack storage while looking up). Mine was held with three pieces of fabric tape. I couldn't pull it up with my fingers but a plastic pry tool worked well to lift the tape.

I didn't do any 'scientific' before and after testing but just kept doing the same thing I've always done at the same distances and it made a quite noticable difference.

Before: When I pressed the lock or unlock button the van responded on the first press about 65-70% of the time

After: When I press the lock or unlock button the van responds on the first press about 90-95% of the time :rad:

Conclusion: Well worth the effort.
 

ENMeyer

Active member
Thanks for this write-up 98Firebird. Just did this modification. Quite easy and seems to work about 50% better and well worth the time.
 

SOLBRTs

Member
Thanks very much for the write up. This explanation led me to lock and unlock with my arm up in the air keys held high. I look like an idiot I’m sure but it’s solved about 75% of my frustration.
 

JFloFoto

Member
First of all, thank you OP. This was a great solution to an annoying issue.

For those interested, I may have come up with an easier method to obtain the same result. Since we're dealing with an antenna, why not just extend it? This avoids taking the dash apart.



I added several more feet of wire to the antenna then experimented with location. Of all the locations (up A pillar and over windshield; up A pillar and around passenger door; and up A pillar along right side of van) the best fix was to simply make the whole van an antenna. I grounded the extension to a screw in the A pillar which also secures the plastic cover. Voila, dramatic improvement in reception... Probably 3 times the range from the rear and back left side. Maybe twice the range in other directions.

Where I attached the extension:









My crude representation of how reception changed:



Hope this helps.

Sent from my Pixel using Tapatalk
 
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First of all, thank you OP. This was a great solution to an annoying issue.

I grounded the extension to a screw in the A pillar which also secures the plastic cover. Voila, dramatic improvement in reception... Probably 3 times the range from the rear and back left side.
...

You shorted the antenna to chassis? What was the length of your extension? I'm thinking about the math that makes this work correctly.
 

JFloFoto

Member
I'm thinking about the math that makes this work correctly.
I didn't do any math ;) Just experimented. The extension was ~3-4'.

Was in the empty parking lot at Home Depot tonight. I was almost 100' away off the driver's side quarter panel. It unlocked easily.
 

DirtDogg

Member
Absolutely, I made this in response to the keyless remote performance thread. The original location of the antenna is not ideal and performing this repair allows for a larger remote range. They found the problem (I'm assuming after looking into it after multiple complaints) and came out with the procedure as a remedy. They do not make it clear or not if they are changing the procedure at the factory level (I personally doubt they are changing the installation position at the factory). As far as testing I have not had a chance to test it myself yet, the van I did this on has the engine apart with no battery in it. Pictures should be fixed let me know please.

Can confirm if this is a factory bulletin?
 

DirtDogg

Member
Luckily my '17 (built 12/30/17) has good FOB performance as delivered so far.

I locked the van doors from my bathroom window, about 60ft away on the 2nd floor.

I wonder if they have updated this at the factory?
I have '17 built in Nov. I can confirm my FOB works like poop. Especially from the rear of the vehicle.
 

Thump_rrr

New member
Do any of you have a factory cargo divider?
All of mine have cargo dividers and the reception is definitely poor.
I didn’t notice this thread before so I will be performing the modification most likely later today.
 

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