automatic pairing

[samburns]

I have a mex-bt3900u I am  able to pair with iphone4 but when I leave and then return to vehicle I have to pair again. I am not asked to put code in when paired .Would like automatic pairing when I get into vehicle. Any suggestions?

[Convergence]

The head unit is always active (unless you press the BT button), this would only leave an issue with your phone, I use the same set up and mine connects automatically without issue, although sometimes the Audio side takes a while, but the hands free phone connects instantley, and is much quicker since iOS6

[Tufftybob]

Hi samburns,

Since it is currently July 2014 I would seriously hope that you would have found a solution by now, but just in case you have not here is my suggestion:

1) Connect your head unit face plate to the head unit, and switch it on.

2) Press the BT (Bluetooth button) to switch on bluetooth on the head unit. (BEFORE you remove the face plate of the head unit and/or switch the head unit OFF, make sure that Bluetooth is STILL active).

3) Switch on bluetooth on your iPhone.

4) Wait for the iPhone to pairwith your head unit, then wait for it connect to your head unit. You will know it is CONNECTED because the bluetooth settings will show 'sony automotive - connected', or something similar.

5) Pairing is NOT the same as connecting. Pairing only needs to happen ONCE.

6) Connecting is what happens after the devices are paired.

7) Your iPhone may well pair, but that does not mean it will connect.

😎 If your iPhone pairs but does not connect, then you will not be able to stream music from the iPhone to the head unit or do anything ese that the head unit is supposedly capable of doing when connected to the iPhone.

9) If your iPhone DOES connect to your head unit, then the display of the head unit should have FIVE icons at the right hand end for Bluetooth, Phone, Music, Signal (mobile network or bluetooth? - I am not sure), and Phone Battery.

NEXT (if you want to stream music):

10) Use the source button on the head unit to scroll to BTA (bluetooth audio).

11) Then use the iPhone 4 to select and play your choice of music, as you would normally.

12) You would then control the volume of the music via the head unit, because the iPhone volume buttons will not or may not work.

If you want to use 'bluetooth hands free features' for phone calls received or those you wish to make:

13) Scrolling to 'BT Phone' should show up any name given to, or assigned to, the iPhone when it was set up, which proves it is connected to the head unit,

14) When this source is selected I would have thought that it should also allow the use of the quoted 'hands free features', listed in the user manual for the head unit, but don't quote me on that.

Hope this helps

Bob

[Tufftybob]

Hi samburn

The next thing to do (which I forgot to mention) is that you would switch bluetooth ON (on your iPhone) each time you wish to CONNECT it to your head unit - each time you get in your car.

If your head unit is switched on AND bluetooth is active on it, the phone will or should connect automatically.

(When bluetooth is active on the iPhone)

It may even connect to the head unit when it is 'off'', as the five previously mentioned icons are still visible on the display when bluetooth is still active when the unit is turned off AND they appear on the display again when the face plate is re-connected to the head unit but before it is switched on. I would not expect to be able to use the hands free feature to accept any incoming call, make a call or obviously stream any music to the head unit, in this situation

If bluetooth is NOT switched on on the head unit, then switch it on (press the BT button) and don't switch it off.

You may also wish to leave bluetooth ON, on your phone all the time, but this would drain the batterey quite quickly, I would think.

If the phone is NOT connecting to the head unit, despite bluetooth being on, on both the head unit and the iPhone, perhaps because the phone is really not actually paired at the time, (even if it WAS previously paired), then the phone and/or the bluetooth software would maybe, either be faulty or someone accidentally UNPAIRED the iPhone from the head unit, if they accidentally deleted the bluetooth profile for the head unit in the bluetooth settings on the iPhone.

Remember that pairing is not the same as connecting. Pairing should only need to happen once. Some bluetooth devices may well pair with each other but that does not mean they will connect.

e.g.

My previous HTC Desire smartphone was listed as being compatible with my top of the range Tom Tom Bluetooth enabled Satnav, but it NEVER connected despite being paired DOZENS times.

Bob