4 Replies Latest reply: Mar 12, 2013 11:23 AM by McGuinness_CGN
McGuinness_CGN Level 1 Level 1 (0 points)

Hi fellow iPhone users,

 

I have a question regarding Bluetooth (BT) connectivity when the iPhone 4 (iOS 6.1.2) switches to standby.

 

This is what I observed:

 

I have a JVC KD-R741BT car radio which uses BT to act as a hands free kit. Furthermore it supports audio streaming.

 

Pairing the radio and the iPhone was not a problem. Also telephone and music streaming works fine. But if the connected iPhone goes into standby (no active call and no audio streaming) the BT connection gets lost around 30 seconds after the lock screen switches on.

 

I doubt that this is the radio's fault because I tested the radio with another phone and the connection stayed alive even when the phone idled. Vice versa I tested my iPhone with another car kit (SIEMENS HKW-720 and I got the same result - around 30 seconds after the lock screen the connection was terminated).

 

Then I did another little test with my MacBook Pro (MBP). First I connected an iPad 2 (iOS 6.1.2) to the MBP and switched on the iPad's lock screen. Even after 15 minutes in standby the BT connection was still alive (according to the MBP's BT device manager).

 

Then I wanted to try the same with the iPhone. However, I was not even able to connect at all. According to my MBP, pairing was successful. Both devices appeared on their lists of known devices. First, I clicked on "Not connected" (I don't know the exact English wording because my iPhone's language is German... ). But instead of changing to "Connected" I got: "Connection failed - "macbook" is not supported. - Ignore device." Trying to connect from the "other side" brought up the following message on my MacBook's screen: "The Bluetooth network is unavailable. - There was an error connecting to your device's network. Make sure network access is enabled and available on your device."

 

So the questions are:

 

Why I can not connect my iPhone to my MBP at all? And why will the BT connection be switched off when the iPhone switches to standby? I doubt that this is the intended behaviour...

 

Oh, and I checked the log files. I have many "BTServer" incidents there. In most cases the BT PowerMgr crashed... Maybe this information helps...

 

Cheers

McG


iPhone 4, iOS 6.1.2
  • 1. Re: Should Bluetooth stay connected when iPhone is on standby?
    KiltedTim Level 8 Level 8 (37,815 points)

    McGuinness_CGN wrote:

     

    So the questions are:

     

    Why I can not connect my iPhone to my MBP at all? And why will the BT connection be switched off when the iPhone switches to standby? I doubt that this is the intended behaviour...

    Because that is not and never has been a feature of the iPhone.  You can't pair it with any computer except for tethering.

  • 2. Re: Should Bluetooth stay connected when iPhone is on standby?
    MLadd Level 3 Level 3 (645 points)

    The iPhone can only tether with another computer.

     

    As for your radio, it sounds like an issue with that system in the vehicle. I have used 4 generations of iphones in a number of different vehicles with BT capabilities and have never had an issue with the connection dropping after the screen locks, even with nothing streaming and no calls for hours.

     

    You may want to check the settings on the radio to see if there is something going on in there. Are you connected to the USB ports also? If so, it may be trying to use that port instead of Bluetooth for those features. I know when connected via USB I sometimes have to switch the selector on my radio back to bluetooth.

  • 3. Re: Should Bluetooth stay connected when iPhone is on standby?
    McGuinness_CGN Level 1 Level 1 (0 points)

    Ok, I know that BT is kinda limited in the iWorld but the phone should still be able to connect to the computer if I would want to use it for tethering, or? Is there really a difference between the iPhone and the iPad in that matter (because my iPad connected to the MacBook without problems)?

     

    Anyway, that my phone can not connect to my MBP is just something I noticed while investigating and for me personally not something I really care about. More important is the above mentioned standby issue because I really would like to be available for incoming calls without having the phone in my hands while driving (which can get expensive in Germany... ).

     

    @ MLadd:

     

    In my opinion the radio is not to blame. I just spent ten minutes freezing in my snowed in car with my iPad (iOS 6.1.2 as well) connected to the radio and the connection kept alive despite the fact that the iPad was in standby. The iPhone however, canceled the connection again after 30 seconds.

     

    No, I did not use the USB port. However, I noticed if I plug the iPhone to a power source (radio or the car's 12V power outlet with a car charger), the connection stays alive even with the lock screen switched on. Another thing I just observed: If I set the auto lock screen to "never" it also stays connected.

     

    Those are workarounds but not more because the advantage of a BT car kit is that I can leave my phone in the pocket without having to use a cable (and charge) it all the time.

     

    Hmm, when it works while the iPhone is connected to a power source and in the iPhone's log files there are incidents where the BT PowerMgr (I guess Mgr stands for Manager) crashed it might be connected to my problem. Can it be that I am dealing here with a HW defect?

  • 4. Re: Should Bluetooth stay connected when iPhone is on standby?
    McGuinness_CGN Level 1 Level 1 (0 points)

    Update:

     

    I just restored my phone without loading a backup so everything was "clean". I tried again but the reset did not change anything.

     

    I noticed that in the moment the iPhone connects to any other device via BT, the BT PowerMgr crashes.

     

    So to really rule out that it is a problem of the radio I just did a last test: I created a personal hot spot and connected the iPhone with my iPad. Everything worked fine. On my iPhone's display it showed that there is one active connection. On the iPad's display the icon in the upper left corner which shows that the device is connected to another device appeared. Then I activated the lock screen on the iPhone and after exactly 40 seconds the connection icon dissapeared from the iPad. Afer I unlocked the iPhone I saw that it still displayed a connection to the iPad but just for a few seconds.

     

    This is getting really frustrating for me...