EZPass Interference

[randypk]

Can an EZPass cause interference if mounted too close to a radar detector?

[tjbender]

It shouldn't. EZPass is a completely passive device that, to my understanding, doesn't broadcast any signal whatsoever.

[kpatz]

Correct. The EZPass transponder only "transmits" when it receives a signal from the booth. The booth's signal actually powers the transponder. Outside of there, the EZPass does nothing.

The frequencies are totally different from those RDs use.

You can read more on RFID which is what EZPass is based on here: Radio-frequency identification - Wikipedia, the free encyclopedia

[crazyVOLVOrob]

There is no interfearance I have always run my detector right next to my Ezpass with no issues

[BreakfastPirate]

To my knowledge, EZPass technology is "Active RFID" meaning that it uses a small battery to power the transponder. Perhaps they changed it in newer models? I remember people having to replace batteries on their IPasses in Illinois.

That said, I've had no interference from mine and use it almost daily.

[Davis]

EZPass is indeed an active system, that's why the batteries need to be changed: to supply the self continted trasmitter. Passive stickers look like this: and are almost always not transferrable from car to car. In both cases, I've never recieved any dtectable interference from either type of tag, at tolling plazas or otherwise.

[kpatz]

AFAIK the NH EZPasses have no battery. Unless it's sealed inside the transponder, but we've had our transponders for almost 5 years now and no need to change a battery *yet*...

[jfuredy]

So most of the EZPass badges are RFID units? I wasn't sure that they had the range to be useful in a passing car.

Joe

[Davis]

All of the EZPass units are RFID. The ones in a plastic shell that have some width to it will have a battery. These are active RFID transponders and will actively transmit a signal using power from the onboard battery. The batteries will have a significantly variable lifetime based on usage patterns and conditions. The sticker type tolltags that are affixed to your windshield and never removed and passive RFID transponders. They draw their power from the toll collection station, and this is what they use to send their responding signal. This is no battery, and they cannot be removed and need never be replaced.

[lugnuts]

AFAIK the NH EZPasses have no battery. Unless it's sealed inside the transponder, but we've had our transponders for almost 5 years now and no need to change a battery *yet*...

they do have a battery sealed inside. I got a letter a few years ago from EZpass that my battery was low and that they were sending me a new transponder and to send the old one back in the provided envelope