Carnetix P1900 Ver. 2.2 w/Mac Mini Core Duo - Startup Problems

mrclean12 · 07-20-2006, 03:54 PM

I just got the Carnetix P1900 Ver. 2.2 power supply from mp3car that I am using with my Mac Mini (Intel Core Duo 1.6Ghz). I got the Power Button cable (with Y adapter) connected with no problems (I'm using the MacPac cable).

When I apply the "ignitiion" to the power supply, the power supply fan spins up and the red light begins to blink (meaning it's in "bootup lockout" mode). The power supply is then supposed to send the signal to the computer to power up, but my Mac Mini never comes on. If I manually press the power button after a few seconds, it does start up (i.e. the power supply is properly supplying power to the Mac Mini...it just didn't "switch" it on via the Power Button cable). Once I turn the ignition off, the computer properly begins the shutdown process. This tells me that the Power Button cable is correctly hooked up since it DID receive the shutdown pulse, it's just not working for start up...

To make sure it wasn't just a delayed bootup, I waited about 2 minutes and the machine never booted up on it's own. With the machine still off, I turn "ignition" back off. Within a few seconds, the machine starts to boot up! I'm assuming the ACPI (power on) pulse (normally for shutdown) is being seen by the Mac Mini, so it begins its bootup. However, the power supply is now in shutdown mode and turns off the power after 60 seconds. I believe I have the Power Button wired correctly to the power supply since the Mac Mini saw the pulse when the power supply was trying to signal a shutdown.

Anyone else having the problem I'm having? Anyone successfully get the p1900 working with a Mac Mini Core Duo? How about specifically getting v2.2 of the p1900 working? Could there be something I'm doing wrong?

Sorry for the long drawn-out post. :-) Any help would be much appreciated!

Thanks,
Brian Doherty

MikeH · 07-20-2006, 05:33 PM

Just to add my 2 cents.....

Brian *has* asked us if we've seen this phenomenon, and we have not. If anyone has had experience with the Mac Intel + P1900 (any version, the startup delays are all identical) please let us know. Are you experiencing any intermittent startup issues? Does you Mac exhibit the symptoms Brian describes? Feedback appreciated....

Jagwire · 08-01-2006, 04:29 PM

this happens to me too, and i've already posted in the carnetix forums as well :-/ any advancements?

GoHybrid · 08-01-2006, 04:53 PM

i am running a p1900 v2.1 with an intel core duo mini. No problems at all. I desoldered the R46 resistor, flipped the board over and soldered an 1/4W 3.3K resistor between the iSense and GND pins on the harness receptacle. I bench tested with a 12V hobby battery. I connect PWR and GND... nothing as expected... then apply 12V to the yellow IGN wire... boots right up. No problems at all. Take away IGN.... if it's not in lockout, it shuts right down. It works great. Soldering the resistor to the bottom of the board i think is key because it's pretty easy to get a cheesy solder joint at the top that pharks up the resistance... not to mention you don't have to cut into your mac pac cable. There's plenty of clearance and a nice plastic insulator underneath the board too.

Jagwire · 08-01-2006, 04:56 PM

i've got the p1900 v2.1 with a core solo and macpac. I did the 6.8k resistor mod and everything seems to work besides the initial startup pulse sent to the mac, i'm not sure whether or not i want to take off the 6.8k resistor and R46 and just replace them with the 3.3k maybe if someone can confirm this is the problem...

GoHybrid · 08-01-2006, 05:25 PM

part of me thinks that since resistors have a tolerance and not an explicit value, using two resistors in parallel could create a larger deviation from the target value than using a single resistor. I imagine if the resistance gets too far outside of what iSense is looking for, you might have intermittent issues depending on the joint quality, temperature, actual resistor value etc...

gmcwv · 08-07-2006, 08:31 AM

I have the very same issue as mrclean12. I have the same setup as well (ver. 2.2) As of right now I have to switch the mini on by hand...and that aint fun. Anybody get any ideas yet on what is the issue?

godraj · 08-10-2006, 03:51 PM

I'm having the same issue. But to go into more detail: if the mini is sleeping when the car is off, applying ignition will wake the mini up. However, if the is shut off while car is off, applying ignition will NOT turn on the mini. I have version 2.1 of p1900 with a 3.3K resistor on the underside of the board.

spinerep · 08-12-2006, 10:03 PM

same problem, ver 2.2. This is the last part of my intial set up that is not working just right yet. Any luck yet.

Jagwire · 08-12-2006, 10:57 PM

i had to install an external power button that sends the short signal to the motherboard because the p1900 wont start it up when i turn it on

it works but i wish it would work the way it's supposed to

snoslicer8 · 08-20-2006, 10:17 PM

I have the P1900 and an Intel Core Solo Mini. Mine has never cold booted from scratch when I turn on the ignition. If the computer is off, and I turn OFF the ignition, it will start up. I do not cold boot however, since I never go a day without driving my car.

I set my mini to allow the power button to sleep the computer. I also disabled the option that says "restart automatically after power failure." It works well...wakes up on ignition, goes to sleep 16 or however many minutes after I shut the car off. Allows for leeway when I leave the car for just a minute.

go0gies · 08-27-2006, 04:27 PM

i also am having these problems. One time i got it to work by disconnecting the switch y cable to the mini and turned it on manually while starting hte ignition and then connecting the cable back so that it would shut down normally. However this only worked once and i have not been able to reproduce the solution. I have a ver 2.1 pcb with the macpac kit and a dual core mini. i also took off r46 completely and isntalled a resistor on the bottom like the instructions said. any help would be greatly appreciated...

thanks

nvrau · 08-28-2006, 08:34 AM

Why are so many of you using this part if the manufacturer can't get it to work right?

Is there no alternative...

B.

gmcwv · 09-05-2006, 11:44 AM

They are supposed to have a fix for this, I just updated my board with the new programming so we will see what happens. Visit CarNetix support site for the fix. Here is a link to the post

http://www.carnetix.com/forum/showthread.php?t=589