what does E mean on signal strength indicator?

It means you're on "Edge", which shows you've got 2/3rds of 3/8s of diddly-squat in terms of cell coverage. Has nothing to do with the car's energy saving mode.

I believe it means that you are out of range of the 3G network and are instead on AT&T's "Edge" network, which is very slow compared to 3G.

I'll go with Scott and say it is related to Energy saving mode. 2 reasons:

1) I'll pull into my work parking, and have full 3G bars. Slacker and Nav still work. 8 hrs later, when I start the car, E shows up for the signal strength. (even though I am in 3G coverage area).
2) The behaviour I described above stopped when I turned off energy saving mode.

It's edge. It's possible that when the car is in energy saving mode it falls back to edge to conserve energy. Try this: turn on always connected. I bet it stays in 3G.

My kids call that the Extremely slow network..

The E stands for EDGE or Enhanced Data for GSM Evolution.

This is a legacy cellular data protocol, faster than GSM but slower than 3G. Sometimes it's referred to as "2.5G."

The car's cellular modem will drop back to EDGE when the car is in a weak AT&T signal area as 3G requires a stronger carrier signal than EDGE. It could also mean you are in an area with older tower equipment that doesn't support 3G, but there's nearly none of this left in the US. I'm not so sure about Canada.

While EDGE transmission uses less power than 3G, it's a difference measured in milliwatts and only significant on cell phones with tiny batteries measured in milliamp-hours. I can assure you that your car with a battery measured in killowatt-hours (a million times larger) is not dropping back to EDGE by choice to save power.

At various versions iOS and Android smartphones have shown the same thing on their cell status icons when in marginal coverage and dropping back to EDGE. For example:

http://www.imore.com/sites/imore.com/files/images/stories/2008/09/iphone_21_3g_edge_icons.jpg

Just be happy that is not showing G (GPRS) as that's even slower :scared:

Mark Petersen said:

Just be happy that is not showing G (GPRS) as that's even slower :scared:

Click to expand...

Evidently the programmers in California couldn't conceive of anything slower, since when connected to a GPRS network it still shows "E".

The network Tesla uses in the UK (O2) has limited 3G outside the cities, and their 2G network doesn't offer EDGE.

I always use Energy Saving mode and have never seen an E on the display as you describe. I am in an area of strong 3G and LTE coverage. Even when I'm in a bad reception area, I've never seen the display switch to E.

The E means the Edge network. Slower than 3G.

I wish there were an "asked and answered" flag for these question threads. Folks, this one has been definitively answered, but let's see if we can get another page! :biggrin:

E means Edge network

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Can someone else also confirm that?

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