2013 Prius Problem with Galaxy s4 Bluetooth connection

I do not have the exact answer, but I would venture that it is probably going to be one of two things.

1) the contact information is saved on the phone in a different format or 2) the contacts that are not showing up are saved on the SIM card and not on an gmail or other account on the phone itself.

First, unfortunately because of the open nature of android, there will always be compatibility issues (think about windows vs mac for PC). You will probably notice that the address book on the LG phone is different from the one on the Samsung. It is possible that the contact information is being saved in a different format if the contact was generated on the phone itself vs one from gmail, yahoo, or outook.
Second, If you have had the SIM card that you use for some time (especially if you had it in an older "dumb" phone) it is possible that you have contact information that is saved to the SIM card, and not the internal phone memory. It is possible that the Entune system is not able to read this even though the address book app on the phone can.
When you look in the address book on the phone it will indicate what contact type they are. For example, if you have multiple google accounts set, it would indicate which one they belong to. Also if you were to have an exchange or other account that will be noted. Then there are contacts stored on the SIM card. Are the ones that do not show up all of the same type?
If the contacts that show up in the car are assigned to one account, and the ones that do not show up are assigned differently, you should be able to edit the contact and change what account they are associated with. If there are contacts that are only on your SIM card, and not saved to google, or another cloud based account, I would highly recommend moving these contacts over so that in the event of loss of the SIM, you do not lose the contact information.
I don't think there is much that can be done about the format that the contacts are displayed, but hopefully we can help to determine why some of the contacts are not showing up. I find that using the voice command to dial usually finds the contact under the person's first name, this may make it easier when you are trying to call someone.

 

Dayl, What version of Entune are you running? Most current version is 3.2 My 2013 only OTA updated to 2.1 I had to download and update the app via USB. This might help with Android issues. Unfortunately, Toyota does not provide what was updated.

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