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CA FasTrak Transponders

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I'm confused. Isn't the transponder supposed to be visible in the windshield to avoid a ticket from CHP?
Technically, yes. IMHO, it depends on what toll roads you travel. Check this thread for some answers about the 10 and 110 lanes where you must have the DMV CAV stickers to get the three person toll free rate when driving solo: Model X Windshield Mounted Sunpass (toll payment device) - (The transponder DOES works in Model X in the position shown in the photo.)

Here is some text from 91 Express Lanes about the subject:

Do I have to mount my 91 Express Lanes transponder on my windshield?
Yes. The California Vehicle Code requires that a transponder be properly mounted on the vehicle's windshield. Keeping the transponder hidden may result in transactions being processed as violations and a citation issued by the CHP.

- - - Updated - - -

I've never heard that. I just set it to 3 and sealed it up under the nose. The Tesla qualifies as 3 person car all the time.
It's a three person car for solo drivers only on the 10 and 110 freeways with the 3 person transponder and you have the DMV CAV stickers. (Not sure about NoCal locations, check with the agency that runs your toll roads for details.)

Just don't try driving solo and use the 3 person lane on the 91 Express Lanes. The 3 position switch isn't used on that toll road. The only way to get a free or discount solo driver toll on the 91 and no monthly transponder fee is to apply for a Special Access account for ZEV vehicles when obtaining a FasTrak for all roads in California. It's only available at this site: https://www.91expresslanes.com/signup.asp - Click on "Download Application". (You can also have 3 people in your car for the free or discount toll. Look for the small print in the FAQ section.)

Account holders with three or more people traveling in their vehicle travel toll-free except Eastbound, Monday through Friday from 4-6 pm. During this peak time carpools of three or more receive a 50% discount on the posted toll.
 
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Technically, yes. IMHO, it depends on what toll roads you travel. Check this thread for some answers about the 10 and 110 lanes where you must have the DMV CAV stickers to get the three person toll free rate when driving solo: Model X Windshield Mounted Sunpass (toll payment device)

Here is some text from 91 Express Lanes about the subject:

Do I have to mount my 91 Express Lanes transponder on my windshield?
Yes. The California Vehicle Code requires that a transponder be properly mounted on the vehicle's windshield. Keeping the transponder hidden may result in transactions being processed as violations and a citation issued by the CHP.

- - - Updated - - -


It's a three person car for solo drivers only on the 10 and 110 freeways with the 3 person transponder and you have the DMV CAV stickers. (Not sure about NoCal locations, check with the agency that runs your toll roads for details.)

Just don't try driving solo and use the 3 person lane on the 91 Express Lanes. The 3 position switch isn't used on that toll road. The only way to get a free or discount solo driver toll on the 91 and no monthly transponder fee is to apply for a Special Access account for ZEV vehicles when obtaining a FasTrak for all roads in California. It's only available at this site: https://www.91expresslanes.com/signup.asp - Click on "Download Application". (You can also have 3 people in your car for the free or discount toll. Look for the small print in the FAQ section.)

Account holders with three or more people traveling in their vehicle travel toll-free except Eastbound, Monday through Friday from 4-6 pm. During this peak time carpools of three or more receive a 50% discount on the posted toll.
Wow! That's complicated. Looks like Tesla qualifies as a 3 person vehicle. I don't go down there so I'll untwist my brain now.
 
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Wow! That's complicated. Looks like Tesla qualifies as a 3 person vehicle. I don't go down there so I'll untwist my brain now.
And it gets more complicated at the other thread. Model X Windshield Mounted Sunpass (toll payment device)

I just reread it and it is confusing, especially when visiting no less than three different agency websites for the details: 91 Express Lanes, The Toll Roads®, and Metro Express Lanes.

Enjoy this video about the Metro Express Lanes and the possible violations for any driver:

 
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For what it's worth, I have a Dec 2013 MS, in SF Bay Area, and both my old transponder and the new Flex version have always worked flawlessly through the windshield mounted next to the rear view mirror.

When not in use, I keep the transponder under the cubby beneath the center console. (For the old transponder, I needed to make sure it was out of range when using the express lane to avoid being charged)
 
I have verified my FasTrak flex tag works through the black space to the right of my rear view mirror in my November 15 Model S. I'm just going to leave it set on 3 there and not put it back in the bag as it's my understanding that ALL of the Bay Area express lane toll areas have been updated for the flex tag so I shouldn't be charged for using say the 880-237 connector ramp so long as it's set on 3.

Jeff
 
I have verified my FasTrak flex tag works through the black space to the right of my rear view mirror in my November 15 Model S. I'm just going to leave it set on 3 there and not put it back in the bag as it's my understanding that ALL of the Bay Area express lane toll areas have been updated for the flex tag so I shouldn't be charged for using say the 880-237 connector ramp so long as it's set on 3.

Jeff

Can you take a picture? I put it up there the other day going across the San Mateo bridge with the switch size under the black since only half the transponder will fit and it didn't work. Thanks!
 
I have a 2013 and have Never gotten any transponder to work in any position from my car front windshield. I think I have tried it at least 10 times and once I think I even opened the roof. I may try the rear window idea next. Does anyone have a photo of where to put this on the rear window? I'm not clear as this thread is very long.
 
I have a 2013 and have Never gotten any transponder to work in any position from my car front windshield. I think I have tried it at least 10 times and once I think I even opened the roof. I may try the rear window idea next. Does anyone have a photo of where to put this on the rear window? I'm not clear as this thread is very long.

There are two locations that I have seen discussed. The first is in the upper right corner of the rear lift gate glass, in the area where there are some antennae embedded in the glass (they look very similar to the wires used for the rear-window defogger, but they don't go all the way across the glass). This is where I put mine, and it's worked on all the bridge toll plazas I've tried. Photo below. (FYI the black square in the middle of the transponder is some heavy duty Velcro that I had used when trying to mount the transponder behind the nose cone, but the transponder in this picture is currently attached using the white "official" Velcro strips.)

IMG_8318.jpg


A week or two back, someone mentioned that technically only the lower right corner of this window was a legal location according to the motor vehicle code. I think the poster who suggested this had tested it successfully.

There might be one other location suggested...I don't remember exactly but I think it was at the bottom of the lift gate glass, near the center? It was somewhere that was not visible to the driver.
 
There are two locations that I have seen discussed. The first is in the upper right corner of the rear lift gate glass, in the area where there are some antennae embedded in the glass (they look very similar to the wires used for the rear-window defogger, but they don't go all the way across the glass). This is where I put mine, and it's worked on all the bridge toll plazas I've tried. Photo below. (FYI the black square in the middle of the transponder is some heavy duty Velcro that I had used when trying to mount the transponder behind the nose cone, but the transponder in this picture is currently attached using the white "official" Velcro strips.)

View attachment 114485

A week or two back, someone mentioned that technically only the lower right corner of this window was a legal location according to the motor vehicle code. I think the poster who suggested this had tested it successfully.

There might be one other location suggested...I don't remember exactly but I think it was at the bottom of the lift gate glass, near the center? It was somewhere that was not visible to the driver.

On my wife's June 2015 S70D without the front windshield black dotted area, I mounted her Flex transponder in the bottom center of the rear liftgate window so it gets hidden from view by the tall center rear seat headrest.
 
Why is it my transponder beeps every time I drive through LAX, even though it is stuck in the glovebox, but can't work on the tollway when I have it stuck to the black spot on the windshield. Whatever advanced tech LAX is using for the taxi/buses etc that sets off the transponder should be adopted by the toll agency.
 
Illegal unless in the window???
I got my transponder several years ago. It was the type that fits on the screws of the license plate. That's not the window. And then, I popped the nose cone and put it on top of the bumper. That's not in sight. And every time I go through an EZPass, I get billed. Amazing!
And I don't have stickers on my car. Never bought em.
I've never had anyone look askance at me as I cruised through the toll gate.
 
I have verified my FasTrak flex tag works through the black space to the right of my rear view mirror in my November 15 Model S. I'm just going to leave it set on 3 there and not put it back in the bag as it's my understanding that ALL of the Bay Area express lane toll areas have been updated for the flex tag so I shouldn't be charged for using say the 880-237 connector ramp so long as it's set on 3.

Jeff

I found out that the Toll Roads transponder worked on SR73 last weekend when held up to the windshield in the black space next to the rear view mirror on my November 2015 build S.
 
Reading this thread, it seems evident Southern California uses minutely different hardware and policies than Northern California, so a lot is different between the two.

I found additional information at Fastrak Toll Tag Placement | Tesla Motors

I have the North California 3 position FasTrak flex transponder, which I switched to 3 (thanks @mspohr et al), and it is rectangular and barcode at top.

I have TeslaVision AutoPilot second generation hardware (aphw2) in my November 2016 Model S 60D. I do not see any blacked out area discussed here or in the manual. From a post on Tesla.com forums saying it's in the manual, I found it in the in car Owner's Manual: Maintenance: Parts and Accessories: Using RFID Transponders, picture attached.

IMG_5330.JPG


However, in this aphw2 car, there is no black spot (the envelope is taped outside the windshield at night and the picture taken from inside, so you can see contrast of the lighting bounced off the envelope, hopefully):

IMG_5331.JPG


(That envelope has the extra Velcro I ordered from FasTrak in preparation for new car; they take weeks to send it.)

I'm going to try mounting it like this for now, upside down per some posts claiming antenna is on right of transponder and nonblocking area of middle aged Tesla windshields is narrower than transponder (but I don't know if mine has such area nor its shape):

IMG_5332.JPG
 
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I have a 2013 Model S and have tried 4 different Fastraks and none of them work. I've even tried holding them up through the pano roof.... I gave up...
Just wow -- that should have worked!

I did use my above posted mounting position once, last night, across Dumbarton Bridge toll crossing in the super duper fast lane (I sort of assume it was titled carpool FasTrak, but don't know for sure), and at ~55MPH it worked fine on a slot suggesting around 35MPH. I won't be able to test more transponders for a long time, though. I think they turn the transponders on on 580 express lanes after I would already be late to work (commute around there starts closer to 2AM than 5AM, and since my work starts at 6AM, being on 580 at 5AM is completely late, and I don't even know when they start the transponders --- 5AM? 6? Who even knows with government these days), so trying to get a hotel there for the night wouldn't really work. But I might try anyway, and see if the transponders are already running by 4AM, and risk coming to work a bit close to the call.

According to Google, it is late:

Google

It says 5AM. UGH they are dumb.

Speaking of dumb, was Dumbarton named after Bay Area Rapid Transit? "Oh, that dumb BART on the bridge!"
 
Anyone tried using the rear pano roof for mounting the Fastrak Flex? Behind the middle bar it would be invisible for front passenger and driver and I assume that the pano roof is not coated with the same material that is on the windshield..?
 
I did th
I have a 2013 Model S and have tried 4 different Fastraks and none of them work. I've even tried holding them up through the pano roof.... I gave up...

I did that and it blew over to the eastbound lane. :eek:
You can call your fastrak customer service line and ask that they put you on the Tesla list which matches your account with your testa. This is a well known problem and they have a workaround, which works fine. Anytime you pass thru a toll, regardless of agency, it will match your plate and charge you (or in the case of select routes like 110, it's free). I highly suggest the multi switch transponder so you get the automatic free toll options. when available. I keep one account, LA metro, and have used it up and down the state and on a variety of freeways, tollways, express lanes and HOV lanes.

@Ulmo pic above also works reliably, but once my dash cam was installed, no more toll pass.
 
I'm going to try mounting it like this for now, upside down per some posts claiming antenna is on right of transponder and nonblocking area of middle aged Tesla windshields is narrower than transponder (but I don't know if mine has such area nor its shape):
View attachment 206367
Update:

It's been working very well there. I have crossed many bridges and been in many toll lanes, and they all worked flawlessly.