won't boot in car

jrbless · 08-20-2002, 02:23 PM

I'm most of the way done with the software I'm writing for my car music player and went to test it in the car. In the house (using an AC->DC PSU) the computer boots up perfectly and starts playing music, no problems. When I take things out to the car, it POSTs and the fans run, but no music. When I hooked up a monitor, I get the initial screen for the BIOS check, memory check, etc. Then the screen goes blank like normal when it starts loading Windows 98se, and it just sits there. I can't tell if it's accessing the laptop HD or not because it doesn't make any noise when it's being used. The fans keep running w/o interruption and the monitor still is detecting the vga output of the motherboard.

I'm using a Sproggy 2.6 for the PSU. To get power to it, I cut up a 10 foot (3 meter) extension cord. One end of it is wired in the fuse box for the fan/ac unit on a 30 Amp fuse (way more than what's needed). The other end of it connects to the Sproggy. Is this an amperage problem due to the extension cord wires being too small (I think they're 16 guage wire, but not sure).

Any ideas???

Thanks,
James

Paladin · 08-20-2002, 03:34 PM

Im not too sure but have u tried hooking the psu to the car and checking the output current and voltage? and then connect it to you ac-dc psu and cross check both? It might be an old car battery thats giving to lil juice and preventing the harddrive from spinning. If i recalled correctly, somewhere in this forum someone mentioned that the harddrive needs a lil extra juice just to start spinning. Hope it helps..

Paladin

ShinkunoNamida · 08-20-2002, 03:55 PM

the laptop drive should be using 5v so It shouldn't really be a problem from the battery... you might want to check your output on the 5v line though

ODYSSEY · 08-21-2002, 01:16 AM

Go to Wal-Mart. In the car audio section there are amp install kits. Buy the 200 watt amp kit or the 300 watt amp kit. Both are the same price so grab the 300 watt kit, better gauge.

I had a problem with my hard drive spinning down... I replaced the power cables with the 200 watt kit, and now I have NO power issues. Also I can now start my car with the computer on and it doesn't reboot.

Edit: I'm wired directly to the battery, you might want to try that too.

phil.45 · 08-22-2002, 09:23 AM

Quote:

Originally posted by jrbless
To get power to it, I cut up a 10 foot (3 meter) extension cord. One end of it is wired in the fuse box for the fan/ac unit on a 30 Amp fuse (way more than what's needed). The other end of it connects to the Sproggy. Is this an amperage problem due to the extension cord wires being too small (I think they're 16 guage wire, but not sure).

If your talking about a mains extension cord then thats your problem. I once tried this in my early car audio days to run an amp, then thought "wow my amp distorts really early and is not at all loud". Then I replaced the crappy mains cable with proper gauge power cables and it was like getting a new system!

Mxyzpltk · 08-23-2002, 07:34 PM

I agree with ODYSSEY and phil.45; replace the extension cord wire with something in a larger gauge (say, a nice eight) and your problems will very likely disappear.

Anything electrical requires a certain amount of power to function properly. Power is the product of electrical potential (Voltage) multiplied by current (Amperage). Your home electrical system operates at 120 AC Volts. Your car has only 10% as much - 12 DC Volts. Since power depends upon Voltage and Amperage equally, the car must provide far more current than your home to make up for a lack of Voltage. The sixteen-or-so gauge extension cord wire is therefore big enough for use in your home environment. In your car, however, you require a significantly thicker wire to carry enough current.