Thread: Which is better? Bluetooth or Wifi for OBD device?

depends highly on the software you want to use. bluetooth is pretty generally supported (mostly because you can get bluetooth to show up as a normal serial device). wifi, not so much. It requires the sw to be able to link up ad-hoc to a socket. wifi is also a great deal more power hungry and it's range makes it a security concern.

For those reasons I'd go with a bluetooth one from either obdpro or obdlink.

Don't know why my reply isn't showing

because your a newbie, and they need to make sure that you won't spam the forum into oblivion...so you first 'x' number of posts(only the mods know how many this is) need to be approved by a mod..

why can't you use a usb/serial version? it would be much more secure then bluetooth/wifi, and i believe it would allow for some faster data rates--to some extent..(in either case, i believe the rate at which you can poll the sensors is slower then the format that the pc would recieve the data)

speed shouldn't be an issue. Bluetooth 2.0 is 2Mbits/s and Wifi can be up to 54Mb/s or more depending on the standard. CAN only goes up to 1Mb/s and you won't ever see those kinds of rates when polling on obd-ii data.

Originally Posted by soundman98

because your a newbie, and they need to make sure that you won't spam the forum into oblivion...so you first 'x' number of posts(only the mods know how many this is) need to be approved by a mod..

why can't you use a usb/serial version? it would be much more secure then bluetooth/wifi, and i believe it would allow for some faster data rates--to some extent..(in either case, i believe the rate at which you can poll the sensors is slower then the format that the pc would recieve the data)

Yea I thought it was just the initial post that they monitor. Anyways wrote down a reply and I don't know if I pressed submit or not, because it didn't show. That;s why I asked why it wasn't showing.

My reply was:

what are the benefits of having wifi over Bluetooth? Bluetooth can be connected to almost anything and more devices are equipped with Bluetooth. So why wifi? is wifi faster?

Like I said, I need a wireless obdII device. to hook to my laptop so I can view additional gauges on my screen.

I will be viewing maybe 4-5 gauges, so will Bluetooth be able to refresh fast enough so that there isn't any lag in the gauges?

Is there is huge speed difference between wifi and bluetooth?

Originally Posted by tripzero

speed shouldn't be an issue. Bluetooth 2.0 is 2Mbits/s and Wifi can be up to 54Mb/s or more depending on the standard. CAN only goes up to 1Mb/s and you won't ever see those kinds of rates when polling on obd-ii data.

so why is there wifi?
also thanks

i think i only confused you more..

it doesn't matter what you use, as the data rate coming out of the car is slower then either format.

neither bluetooth, or wifi will slow down the connection.

but--because the car can only spit out so much data, this will affect the refresh rate of each gauge. for each gauge that you want to view, the car must split up the available bandwidth(1Mb/s) to send that sensor data to the pc. so that means that every gauge that you add will slow down the refresh rate of the other gauges. there is nothing you can do with any hardware you install to correct this...

Originally Posted by Rickys

so why is there wifi?

same reason that automakers make so many variations of 4-wheeled cars-- because what works for some people doesn't work for others, so they need to give options to take over a larger market share.

Originally Posted by soundman98

i think i only confused you more..

it doesn't matter what you use, as the data rate coming out of the car is slower then either format.

neither bluetooth, or wifi will slow down the connection.

but--because the car can only spit out so much data, this will affect the refresh rate of each gauge. for each gauge that you want to view, the car must split up the available bandwidth(1Mb/s) to send that sensor data to the pc. so that means that every gauge that you add will slow down the refresh rate of the other gauges. there is nothing you can do with any hardware you install to correct this...



same reason that automakers make so many variations of 4-wheeled cars-- because what works for some people doesn't work for others, so they need to give options to take over a larger market share.

Thanks for explaining.

very well. I will go with bluetooth for now. I also want to be future-safe at least for a while.

Also which one should I go with? I will keep it plugged in at all times and I need it to have power of so it doesn't drain the battery.

Thanks

I believe obdlink and obdpro support switching off power when ignition is off to avoid draining your battery (even though i think it'll take a couple weeks for one of these devices to drain you). Take a look at the features in both and decide which is right for you.

In practice, neither WiFi nor Bluetooth is quite as fast as USB or Bluetooth. This has to do with latency, and starts being noticeable at faster refresh rates (20+ samples/second. The analogy I like is of a rocket train that departs every hour. It can deliver lots of data very fast, but if you miss it, you have to wait until the next one comes along. Great for downloading large files, not so great for small, time sensitive OBD packets.

Most people choose WiFi over Bluetooth, because they want to use it with the iPhone. In theory, Bluetooth can work too, but Apple requires certification and charges a license fee, so as of today there aren't any vendors on the market, that support it.

Without PowerSave enabled, the scan tool can drain your battery in a matter of days (even one day, if the battery is old and/or it's cold outside).

Vitaliy