p1900 problem

**super-fly** · 03-04-2009, 07:55 PM

I have a p1900, it has been working fine up until about a week ago. I don't know what is wrong. Here is the problem, it turns the computer on fine but it will not sleep correctly. When I turn the ignition off the screen turns off but then comes back on a couple seconds later, sometimes it just stays on, the computer is also not sleeping at this point. It never did this before, when I turned the ignition off it just went off and stayed off and the computer went to sleep.

The screen wouldn't be a problem if the computer slept correctly, but its not. After the screen comes back on like I mentioned, it will stay on for a few seconds and then it will turn off and the computer will sleep like it should. At this point I can still hear the p1900 fan, but then the fan just cuts off and the computer shuts off, the power just gets cut. I've tried it with my valet switch, with the ignition on i flip the switch and the computer sleeps and the screen shuts off like it should. I then wait until the led stops blinking and flip the switch again and the computer wakes and the screen turns on. However, like I said, this is not the case when I turn the ignition off. Any help would be great.

**natedawgg** · 03-05-2009, 10:38 AM

first off i am assuming you are using a mac mini? if so, it sounds like something is trying to kick the mini back into gear. this could be anything from a usb device acting funny or the p1900 not sending the correct signal. i would try unplugging all of the usb devices as these can easily cause the mini to try to come out of sleep (any activity on a usb device will wake the mini). to be absolutely sure i would take the mini into the house and test just to be sure and rule it out as a culprit. I had this same problem with my mini when i had Ubuntu installed. Linux doesn't sleep well and the p1900 could not coerce ubuntu to shutdown, so i would get the cut in power killing everything. if it is the mini not sleeping correctly (unrelated to the p1900) you can try setting the mini to hibernate. to do this in OS X just open a terminal, and type

sudo pmset -a hibernatemode 1

this will set the hibernation mode so that instead of sleep (saves everything to ram) it will hibernate (save everything to disk). with this set the mini will not be awakened by anything but a power button push (signal from p1900). if this is not the problem you can set the mini back to default sleep mode by using the same command above only setting hibernatemode to 3 instead of 1.

if it is indeed the p1900 then it could be several different issues. one thing it could be is a bad battery in your car. i had a battery go bad, and it really messed with my whole startup/shutdown system. you can get a free battery check at anyplace like autozone. one other test you could do would be to mess with the jumpers on the p1900. try setting them to shutdown instead of sleep. and just make sure that everything else is setup exactly right.

i don't know if any of this will be any help. but these are all steps i would take to further the diagnosis. good luck, and keep us posted if find the solution.

**super-fly** · 03-05-2009, 10:52 AM

I think I may have fixed it...the positive battery cable was loose. I tightened it and Ive only tried it once after that, but its working. I will post back after a couple other on off cycles. Thanks.