fbpx
Jump to Forum..

B.U.D.S. Connection Issue

in 912iS Technical Questions 2 years ago

  • Re: B.U.D.S. Connection Issue

    by » 2 years ago

    " ...This module was replaced last October ... which was after ... (the)  last successful download."

    The Plot thickens!
    Always ask yourself," What has changed since the last time it worked?"

    Anything else you're keeping from us?   ?

    Bill Hertzel
    Rotax 912is
    North Ridgeville, OH, USA
    Clicking the "Thank You" is Always Appreciated by Everyone.

      
    Report

  • Re: B.U.D.S. Connection Issue

    by » 2 years ago

    Well, Bill, IF the HIC module circuit board was created correctly, it should only connect the A and B buses together and pass through, which was why I didn’t pay it much attention, but something is obviously wrong, so to your point, assume nothing.  See attached snippets from Van’s schematic.  You can see that Van’s doesn’t carry a dedicated ground through the connector; they use the shield as the ground.  But the HIC module is definitely common to both of the aircraft for which I’ve not been successful in connecting and was not in the system when Lockwood was able to successfully connect my dongle to their ECU, so it is a suspect.
     
    Still waiting for someone on VAF with a new HIC module to confirm if they have successfully downloaded their logs - no responses after almost two days now.  And nobody with a 12iS on this forum has chimed in either. 
     
    I ran the tests you suggested.  Here are my results:
     
    Unpowered resistance across pins 2 & 7 - 63 ohms, so it appears only two terminating resistors.
     
    All voltages listed below are referenced to ground…
     
    With master on, but Lanes not powered: 1.38 V at both pins 2 & 7
     
    Lanes powered but not connected to the dongle: 2.51 V on pin 2, 2.35 V on pin 7
     
    Master on, dongle connected, BUDS program running, but Lanes off: 2.46 V at both pins 2 & 7
     
    Lanes powered, dongle connected and BUDS running: 2.54 V on pin 2, 3.39 V on pin 7.
     
    I expected pin 7, Hi, to have read consistently higher than 2, but that wasn’t always the case, so the data seem inconsistent to me.
     
    So, what’s your expert assessment?
    36186_2_2023-05-10 06.25.05.jpg (You do not have access to download this file.)
    36186_2_2023-05-10 06.26.12.jpg (You do not have access to download this file.)
      
    Report

  • Re: B.U.D.S. Connection Issue

    by » 2 years ago

    Problem solved!!!  The new HIC module has the HI & LOW lines REVERSED!!!  I just swapped them and it’s now working fine.

    As you said, Bill, “assume nothing”.   As always, thanks for your support and sharing of your knowledge and experience.  

    Thanks again. 

      
    Report

  • Re: B.U.D.S. Connection Issue

    by » 2 years ago

    It appears my earlier post was incorrect where I stated;

    Ref.  DB9  Connector CAN-Bus Pinouts.
    Pin #2 = Ground
    Pin #3 = CAN_Low
    Pin #7 = CAN_Hi

    It should have been;

    Ref.  DB9  Connector CAN-Bus Pinouts.
    Pin #2 = CAN_Low
    Pin #3 = Ground
    Pin #7 = CAN_Hi

    I have corrected the earlier post so this bad info does not get propagated.

    Bill Hertzel
    Rotax 912is
    North Ridgeville, OH, USA
    Clicking the "Thank You" is Always Appreciated by Everyone.

      
    Report
You do not have permissions to reply to this topic.
Related Topics
Title Category Replies
914 TCU Calibration issue 912 / 914 Technical Questions 10
B.U.D.S. Log Data Disposition 915iS Technical Questions 2
Engine start issues 912 / 914 Technical Questions 13
914 MAP issue 912 / 914 Technical Questions 0
Carb Issue 912 / 914 Technical Questions 10

info@rotax-owner.com