Page 1 of 2 12 LastLast
Results 1 to 10 of 17

Thread: Odd behaviour from ITPS

  1. #1
    Maximum Bitrate SAScooby's Avatar
    Join Date
    Feb 2004
    Location
    Johannesburg, South Africa
    Posts
    535

    Odd behaviour from ITPS

    Hiya All

    I have wired up my carputer and got it all installed and am having issues with power i think !! ! !

    I have ITPS and PW70A

    On ignition switch on the pc boots all ok (have some software issues to solve and touchscreen drivers but no biggies)

    Then when I switch the car off, the ITPS does its thing (you can hear it)
    PC switches off and then reboots imediately but since the switched input is not present, the pc can only get into the bios there isnt enough power to drive the HDD / DVD etc

    How do I stop the ITPS trying to boot again ?

    I have measured on a voltmeter and my acc line takes a long time to drop to below 1 volt, even after 10mins the voltmeter still shows .35 of a volt and I am thinking this has to do with the ITPS restart as it still sees "voltage" on the acc line ? or am I wrong ? what can I do to zero the acc line or isnt it important to have that voltage at zero ?

    my acc line is also the same line from the remote turn on on the amps is this maybe the problem ?
    Nano ITX / 512 MB / 60 GB / Panasonic slot load / M1-ATX / Bu303 / Sound blaster 24 / PPi amps / rockford sub

  2. #2
    Constant Bitrate
    Join Date
    Jan 2004
    Posts
    165
    No, using the same line as the remote turn on for your amps is not a problem.

    How is the ITPS wired in? The white line should be the constant +12V line. The red is the switched ACC +12V line. This is how you have it setup correct? And then the small jumper on the ITPS goes to your power switch on your PC.

    If your ITPS was only putting out .35 volt your computer would not even get to the bios startup screen. It would do nothing at all. It sounds like maybe you don't have everything hooked up correctly so double-check your wiring.

  3. #3
    Raw Wave
    Join Date
    Jun 2003
    Posts
    1,823
    I have measured on a voltmeter and my acc line takes a long time to drop to below 1 volt, even after 10mins the voltmeter still shows .35 of a volt and I am thinking this has to do with the ITPS restart as it still sees "voltage" on the acc line ? or am I wrong ? what can I do to zero the acc line or isnt it important to have that voltage at zero ?

    0.35V is low enough as a "LOW" on PIC...this shouldnt retrigger the ITPS at all.

    From what I have noticed the ITPS ACC input is left floating, there should be a pull down resistor from ACC input to ground. Because the input is left floating this can pick up some noise and cause the ITPS to retrigger when the ACC is off.

    To quickly test if this is so, touch the ACC input with wet finger and the other on the +12V. If the ITPS react to this then you know the ACC input is too sensitive...most likely it is left floating.

    Try sticking a 10K resistor between the ACC input and the ground. This should ensure the ACC input is not floating when the ACC is off.

    I may be wrong on this but looking at the original ITPS circuit diagram it is left floating unless they have done something about it by now.

    Try it anyway let us know how it goes

  4. #4
    Maximum Bitrate SAScooby's Avatar
    Join Date
    Feb 2004
    Location
    Johannesburg, South Africa
    Posts
    535
    Hi Unsavory

    It is wired in as per diagram....

    The funny thing now is that the pc works better when my headlights are switched on ! ! ! I am thinking I have insufficient voltage, until the alternator is called upon to deliver more volts / power

    I am going to try the "resistor to ground on the acc line tomorrow and see how it goes.
    Nano ITX / 512 MB / 60 GB / Panasonic slot load / M1-ATX / Bu303 / Sound blaster 24 / PPi amps / rockford sub

  5. #5
    Maximum Bitrate SAScooby's Avatar
    Join Date
    Feb 2004
    Location
    Johannesburg, South Africa
    Posts
    535
    tried the resistor and still the same thing, no shutdown !! ! !
    Nano ITX / 512 MB / 60 GB / Panasonic slot load / M1-ATX / Bu303 / Sound blaster 24 / PPi amps / rockford sub

  6. #6
    Variable Bitrate ryuandwings's Avatar
    Join Date
    Nov 2003
    Location
    TN
    Posts
    273
    Do you have ITPS and mobo connected right?
    There should be a black and red wire with 2pin connector on both end.
    Make sure you have it connected to power botton jumper not reset or something else.

  7. #7
    Maximum Bitrate SAScooby's Avatar
    Join Date
    Feb 2004
    Location
    Johannesburg, South Africa
    Posts
    535
    Hi tried that, it seems as if my switched input does not drop quickly enough to a low voltage, if I manually unplug the switched input + lead, the pc shuts down, I have tried a resistor between it and ground and then a resistor and LED to ground to speed up the process but to no avail, the only way to make the pc shut down is to manually unplug the switched input and then it works as advertised.

    I think I have three options,

    one is to find another ign on lead that drops to 0 quickly enough to trigger the shutdown cycle

    two is build a circuit with a relay in it that drops the switched + input on ign off, so how do I build a circuit that switches itself off ?

    three is to buy an opus

    HELP
    Nano ITX / 512 MB / 60 GB / Panasonic slot load / M1-ATX / Bu303 / Sound blaster 24 / PPi amps / rockford sub

  8. #8
    Variable Bitrate ryuandwings's Avatar
    Join Date
    Nov 2003
    Location
    TN
    Posts
    273
    What is your system setup?
    Like you can see it in my signature, I am using the same ITPS+PW-70 and they are working fine.

    What I did was that I used the same wires powering stock headunt. Basically connected to the factory stereo harness. I got all ground, +12v and ign from that harness. I didn't try to get acc from fuse box. If the picuter is your car, it should be similar to mine. I have 1997 impreza outback sport.

  9. #9
    Raw Wave
    Join Date
    Jun 2003
    Posts
    1,823
    Ok I get your problem now...

    two is build a circuit with a relay in it that drops the switched + input on ign off, so how do I build a circuit that switches itself off ?

    If the problem is exactly how you wrote then the extra relay should work.

    Increasing the triggering voltage of the ACC input on the ITPS should also work...this can be done by a voltage divider.


    EDIT :

    Well...I guess you have some circuit with a capacitor in the car somewhere that hold the ACC line longer.

    Did you try to dishcarge it quicker with a smaller pulldown resistor?

    But then from your original post you said you where able to shutdown OK...

  10. #10
    Maximum Bitrate SAScooby's Avatar
    Join Date
    Feb 2004
    Location
    Johannesburg, South Africa
    Posts
    535
    ricky327 when the prob first arose, I would shut down and it would imeddiately reboot, soon sorted that out with bios changes etc

    But that still hasnt fixed my itps shutdown issue, I think my acc on wire has too many other pieces hanging off it

    I counted them last night

    lili screen egg
    two power supplies for the DVD one at 5v the other at 12v
    one power supply for the IDE -> USB 2 convertor
    one power supply for four port USB hub
    Amp for front and rear speakers
    Sub Amp
    Crossover
    and then finally the pc

    So in amongst that lot I am sure there is something that holds the current up, today i am going to run a new switched + from the key switch to the ITPS
    Nano ITX / 512 MB / 60 GB / Panasonic slot load / M1-ATX / Bu303 / Sound blaster 24 / PPi amps / rockford sub

Page 1 of 2 12 LastLast

Similar Threads

  1. ITPS-Auto Power Sequencer as Shotdown Controller
    By Nellor in forum Power Supplies
    Replies: 31
    Last Post: 03-16-2005, 11:24 AM
  2. ITPS problems
    By numberone in forum Power Supplies
    Replies: 8
    Last Post: 10-29-2004, 04:07 AM
  3. Changing my position o the ITPS
    By adamis in forum Power Supplies
    Replies: 1
    Last Post: 04-24-2004, 07:13 AM
  4. ITPS and Voltage drop issues
    By Wiredwrx in forum Power Supplies
    Replies: 7
    Last Post: 04-20-2004, 06:09 AM
  5. ITPS Power Sequence review
    By saito in forum The Review Palace
    Replies: 8
    Last Post: 12-18-2003, 09:26 AM

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
  •