Forum Discussion
ktmrfs
Feb 28, 2022Explorer III
Retired JSO wrote:
OnStar is satellite, turn by turn traffic avoidance is via cell tower. I understand OnStar will make the updates needed via satellite. Most things other than up to date traffic will not be affected.
NO depending on vintage Onstar uses either Verizon or ATT wireless for cummunication it is NOT a sat system. It uses GPS to determine location, just like a traditional GPS unit, but cell for ALL communications Early systems were CDMA, then 3G, latest 4G There are many many places in the midwest and away from populations where ONSTAR communication does NOT work.
As mentioned below, the car cell phone uses 3 watts instead of 0.6 watts for a handheld cell phone, so it does give better range, but still there are places with limited or no coverage. Worst coverage areas are North south from eastern washington through mid montana pretty much on a north south line. Many parts of idaho and montana have NO coverage for considerable distance and many places with very limited and marginal coverage.
On several of our favorite trips we have 50-75 miles of highway where Onstar communication does NOT have cell coverage (No ATT) and does not function. You can't contact onstar, can't download turn by turn, can't get help, and our kids can't track us.
And many of our favorite out in the boondock campsites we have no Onstar communication either.
That's where the Garmin Inreach Iridium sat communicator comes into use.
take a look at the Onstar coverage map and it will be clear it is not a sat system.
A Quote from Onstar:
At its most basic, OnStar consists of four different types of technology: cellular, voice recognition, GPS and vehicle telemetry. All of the services that OnStar provides are a result of one or more of these technologies working together.
OnStar's cellular service is voice-activated and hands-free. The console contains a built-in microphone and uses the car speakers. To make a call, you speak a phone number or a previously stored name associated with a phone number. The console is connected to a Vehicle Comm and Interface Module (VCIM), which uses a cellular antenna on top of the car to transmit signals to OnStar's cellular network. (For more information on cellular technology, see How Cell Phones Work.) OnStar's cellular service has a better range than most cell phones (although you can still lose service in remote areas), with a full three watts instead of a regular cell phone's 0.6 watts. With some OnStar plans, you can also use the cellular service just as you would a regular cell phone plan.
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