Results 1 to 2 of 2

Thread: Help with Steering Wheel and Ipac!

  1. #1
    Low Bitrate
    Join Date
    Oct 2005
    Location
    London, Ontario
    Posts
    58

    Help with Steering Wheel and Ipac!

    Hi,

    I bought an Ipac to attempt hooking up my steering wheel and am having some serious difficulty. Was hoping someone could help.

    First problem is that I am not sure of which cable is my ground; currently, by trial and error i have found one that generates some results.

    I have 7 cables. Eight buttons (though the Answer and Hangup buttons could be the same).

    So I have connected the 6 wires into different contacts on the ipac and the wire I guessed was ground (white) to the ground.

    I am getting some results; however, the first 4 buttons are all activitating the same trigger on the ipac and the second 4 buttons are activiting a different trigger.

    I really have no idea how to proceed. I have attached a picture.

    If anyone can help I would appreciate it!

    Thanks,

    Shalom

  2. #2
    Maximum Bitrate GoHybrid's Avatar
    Join Date
    Jun 2006
    Location
    Denver, CO
    Posts
    867
    The thing i would wonder about is whether in fact each button is actually connected to a discreet pair of wires. If those buttons illuminate then you probably have a separate power and ground for that, which would leave even fewer wires per switch than you have now. This makes me think that it is like most cars which use a voltage divider network to indicate a different button press over a single wire.

    What I would try is go to pac audio's website and look for information on a unit called the SWI-X. See if your car is listed there. If it is, it will probably tell you something to the effect that that white wire is actually carrying the signal for all the buttons... i.e. it is the ground for the voltage divider network rather than simply a common ground for each button.

    If that's the case then you're in the same boat as I am and you need to employ an A/D converter to interpret the voltage on that signal line and translate it into discreet switch closures that the Ipac can understand.

    One reason I think that this is the case is that as you say, four switches all activate the same trigger. This would suggest that whenever you close a switch, you're closing between the supply (maybe the green wire) and the ground (the white wire). The fact that there is a small (but different) resistor on each switch makes no difference to the ipac, and it just sees it as the same button being pressed each time.

    I don't know why they would use two divider networks instead of one, but if they needed to space out the resistances for reliability, then that would make sense... because if the A/D converter that is reading those switches doesn't have a high enough resolution, or as i suspect, temperature can make resistance vary too widely to have 8 switches on a single line.

    okay... last thing i have for you: check this page: http://www.pac-audio.com/bulletins/swicalculator.htm. It should give you an idea of how this type of network works and also explain the results you're getting.
    Et ipsa scientia potestas est.

    Worklog for my 2007 Civic Si ...f*** it...
    Pictures of the Corolla (retired)here
    Need to make something? Here are a few ideas.

Similar Threads

  1. Replies: 77
    Last Post: 12-23-2008, 08:29 AM
  2. So I have steering wheel controls, 4 buttons... but...
    By mike6789 in forum General Hardware Discussion
    Replies: 1
    Last Post: 08-31-2006, 10:57 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •