Hands Free via Mini ISO port on Symphony CD Players

[bushell89]

Hi guys,

hoping someone maybe able to help me here.

I have a Skoda Symphony CD Player (part number: 6YO 035 156E) and as the title may suggest, I want to add hands free to it to the extent of muting the volume and having the telephone outputted to the speakers. I know that you can get these kits that have all the wiring and a control unit, but part of me thinks that's all a bit overkill.

My phone isn't a common make, it's a Vodafone 710. It has a hands free earphone with a microphone and a button that plugs in though a 2.5 audio jack. My plan is to 'Jimmy Rig' this earphone hands free to the centre Mini ISO port on the cd player by cutting the wires to the earphone and connection them up.

According to a site (More Information - ISO and Mini ISO Wiring Diagram) , this is the wiring guide for the centre Mini ISO port:

7..........10

.....9..........12

8..........11

pins relating to:

7 - Audio Telephone Signal (+ve)

8 - CAN HIGH (second display - clock, for radio sets with CAN databus communications)

9 - CAN LOW (second display - data, for radio sets with CAN databus communications)

10 - ENA (second display - not assigned for displays with CAN databus communications)

11 - REM (Remote Control - not assigned for displays with CAN databus communications)

12 - Audio Telephone Ground (-ve)

From this i can tell I obviously need pins 7 and 12, these would be a direct replacement for the earphone.

For the microphone and button, I intend to remove a spare static button from the dash (next to the rear window heater) and drill 2 holes for a small microphone and push button. Then run a wire to the 2.5 jack, so that these don't need to go to the Mini ISO port. The way the button works is quite clever in the sense that it short circuits the microphone for the time its pressed and programming in the phone interprets this as a button press.

The next issue is the pins 8 - 11. Which if any of these do i need to use?

I was thinking i may need to use pin 11 and connect the button up so that the CD Player knows that the telephone is in use and mutes the cd player volume and outputs the telephone audio.

I'm hoping it'll be that easy, I am very confident with electronic workings so you don't need to waste time explaining in layman terms.

Thanks in advanced!

and sorry for it being a long post.

[VRStu]

As far as I can see you don't need to use 8 or 11. Somewhow you need to interface it with pin 2 on the Black 8 Pin Connector.

This uses 12v to switch to mute.

Fabia-vrs.com - Mobile Phone Car kit Integration

[bushell89]

Cheers VRStu for the quick response, that is a good site not sure how I didn't come across it when I was googling!

I think I'm nearly there then. The speakers are as stright forward as I thought.

With the mute switch I'm gussing that to keep everything muted there needs to be 12v to it at all times. Then when the call ends you can stop the 12v and the volume will return. So now I just need to 'Jimmy Rig' a push switch to act as a push switch to the phone and a constant switch to the radio.........hmmm sounds fun lol

[VRStu]

Just make sure you are happy that it is 12v on your radio I wouldn't like you to get it wrong and blow something up.

[bushell89]

I recogn it would be 12v, most things seem to be based on 12v.

I'll try and google it, see what comes up.

Cheers for the help

[bushell89]

time for a quick update.

finally got the Mini ISO connector i needed from ebay and 'jimmy rigged' up the wiring for testing purposes. I found that the pin 2 for audio mute was not a voltage based pin but needed to be grounded instead. so best was to do that would be to connect that wire to a switch and then to pin 8 of the same ISO connector.

Still working on the rest and will update when i have completed the work.