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Mounting Fastrak transponder

In SoCal, what transponder do you use on your Model 3?

  • Windshield-mounted, top

    Votes: 6 30.0%
  • Windshield-mounted, driver side corner

    Votes: 2 10.0%
  • Windshield-mounted, passenger side corner

    Votes: 3 15.0%
  • Front license plate holder, original Tesla

    Votes: 2 10.0%
  • Front license plate holder, third party

    Votes: 0 0.0%
  • Inside the car, no issues with The Toll Roads

    Votes: 6 30.0%
  • Inside the car, some issues withe The Toll Roads

    Votes: 0 0.0%
  • No transponder, pay toll by plate

    Votes: 0 0.0%
  • No transponder, don't use toll roads

    Votes: 0 0.0%
  • Other

    Votes: 1 5.0%

  • Total voters
    20
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The Toll Roads (SoCal) advised me that Tesla windshields block the regular transponder, so I have to use the external. I ordered the external and it got here. It's bulky and, despite my initial impression, goes on the front plate bracket, not the back. Good thing, too, because that's where the backup camera is.

Some people posted photos that show it mounted. They claim it looks cool, I would go with "inoffensive".

It does appear that the transponder is screw-on, and the front plate holder is a glue-on. Is that correct?

How have others gone about it? Buy a third party plate holder that screws on? Drill holes in the Model 3? (Sacrilege!) Can the transponder be mounted to the Tesla's own bracket somehow?

Also, it appears that the Toll Roads people are wrong about the windshield, that their info pertains to S, but not to 3. True?

Did you mount your transponder on the windshield? If so, top or bottom corner? Can we see photos? Sounds ugly, but one gets used to anything, even carpool stickers.

Did you place the transponder inside the car somewhere? Not what The Toll Roads requires, but I seem to have gotten away with it for 10 years with my MBZ SUV and did not notice any fines or overcharges. Sometimes it beeps, sometimes it does not. The license plate is key.

They told me I can be charged by license plate anywhere but 91. I don't go on 91 all that often.

How did you go about resolving the transponder conundrum for yourself?
 
I have mine mounted inside the car on the glass roof at the very back of the front glass panel of the roof. It works flawlessly through all Fastrak locations.
Not one of the recommended/approved placements, correct? They would have you believe that the transponder has to be visible in the photo they take in case there is a disputed fine/charge. Probably BS.

Any and old photo of all possible placements any of you have opted for will be appreciated.

P.S. I realized that the plastic stick-on Tesla front plate holder has two screw holes for mounting the license plate (duh!). Those holes will fit the transponder. So maybe it's not that much of an issue for me after all. Still, it would be good to learn what more inventive minds have come up with.
 
I mounted mine in the Tesla recommended part of the windshield and have not had any issues whatsoever. I did however request a new transponder when I got the Model 3 so maybe that helps? The new ones the TollRoads send are smaller. If interested, let me know and I'll post a pic.
 
I have the larger East Coast EZ Pass Transponder. Instead of using the heavy duty Velcro-type mounting system, which would require attaching the strip onto someplace on the car, I use a suction cup wire bracket to hold the transponder. It's what I used in my previous car and had no problems EXCEPT in extreme temperatures (Very hot or very cold) where the suction cups would sometimes fail and the whole thing falls down. When it came to my Model 3 I DID NOT want to mount it in the location suggested by Tesla (which is also where I mounted it in my previous car) since if it fell I was concerned it would either 1) Hit the display and damage it and/or 2) hit the wood trim and damage that. By mounting it on the top right corner on the passenger side windshield if it does happen to fall it would miss both the wood trim and the monitor. It is also out of the way and the location works perfectly fine.
 
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This is a picture of the Fastrak placement I described above... it is out of sight behind me, and works perfectly every time.
 

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Anybody try the back side of the touchscreen?? That would flip the transponder front to back, so presumably the antenna would be on the 'wrong' side.

Unless you plastidipped it black, it would look more weird than just in the bottom corner of the windshield.

Sticking it up at the back of the front glass roof is an interesting idea as it'd be really hard to notice. I'm just hesitant cuz I tinted that area and I don't wanna stick anything to it.
 
Unless you plastidipped it black, it would look more weird than just in the bottom corner of the windshield.

Sticking it up at the back of the front glass roof is an interesting idea as it'd be really hard to notice. I'm just hesitant cuz I tinted that area and I don't wanna stick anything to it.
That's why I use separate suction cup bracket holder in order NOT to have anything permanently attached to the glass.
 
The FasTrak conflict with Tesla glass was true of their old transponders and the Model S. But this has been fixed long ago, and the new smaller ones do not conflict with my Model 3.

I've attached mine in a compliant manner, top of windshield, partially obstructed from driver view. It has worked flawlessly for the six months I've had it there.
 

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Boy, there are almost no good options that are compliant and non-ugly. I mounted mine on the front plate holder and boy is it bulky. And ugly. Bulgly.

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When the black vanity plates come it, it may become slightly less noticeable. I will give it a chance and then start looking into inside mounting options.
 
In truth, here in SoCal, one does not need a transponder at all times as long as the licence plate is registered. The Toll Roads person told me I cannot go on 91 without a transponder. I don't go on 91. Well, I will next week, but for that I could probably place an indoor transponder on the dash.

Something on The Toll Roads site says that you need the transponder to pay the best discounted rates. I may have misunderstood that, or they may have put that in as an extra enticement. I ran this by the Toll Roads person, and she said as long as my plates are registered, I will get the discount with or without the transponder. This is corroborated by the fact that, according to my statement, one of my transponders is not working, and all tolls are paid by plate, and they show a $1 discount.
 
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Something on The Toll Roads site says that you need the transponder to pay the best discounted rates. I may have misunderstood that, or they may have put that in as an extra enticement. I ran this by the Toll Roads person, and she said as long as my plates are registered, I will get the discount with or without the transponder. This is corroborated by the fact that, according to my statement, one of my transponders is not working, and all tolls are paid by plate, and they show a $1 discount.

That's my question. The site was saying you want get a discounted carpool rate (some bridges in NorCal still charge for carpool, but give you a discounted rate) or the EV solo (can go toll free on some areas). So, they say you need the Flex transponder and have it set to the EV (or whatever appropriate) setting.

The Flex is just that little rectangle compared to my old giant square transponder, so I'll probably end up sending all my old ones in eventually to get the little Flex ones just for their size alone. I never used the transponders before because I figured the plate was good enough, but didn't know about the discounts and stuff until I started looking into it for the Model 3.
 
In the SF Bay Area you have to have the Flex transponder for the 'pay-to-play' HOV lanes. The old non-switchable ones (including the license plate ones) are no good. Maybe in SoCal you are OK....

Same in SoCal (or at least for The 110). Switchable transponder with settings for 1, 2 or 3 occupants (2 different rates plus free for 3+). For now, if you have HOV stickers, you can leave the transponder to 3.