ITPS not working as expected...

**cyber** · 08-17-2004, 01:11 PM

I finally have everything installed but I'm having problems with my ITPS not working like I thought it would. First, my computer doesn't survive cranking. I turned the key to acc, the computer turns on, and I have a huge grin because I believe I've installed everything correctly. Then I start my car, computer loses power then turns on again. Then after playing with the GPS I turn my car off. The computer INSTANTLY loses power and turns off. I was under the impression that the computer was supposed to still get power for a couple seconds while gracefully turning off. I have the power button jumper cable installed correctly to my M10000. And I'm 99% sure I didn't swap the constant and switched power to the ITPS...but if I had wouldn't the computer stay on all the time? Is there perhaps a BIOS setting or something I'm missing? (I'm running on the defaults right now). Any and all help will be greatly appreciated.

**brooksware2000** · 08-17-2004, 01:45 PM

Okay, do a search in the forum for the ITPS operation. What you are experiencing is native to the ITPS. In all but a few instances it will not survive cranking. Also, if you have 12V devices such as HDD, Cdroms on the 12V bus then it is possible that the computer will reboot as well if your battery is weak. If you have access to a multimeter, check the battery voltage to the ITPS with the car running and with just the ACC line on. I bet there is a noticeable difference. From your description, I don't see any problems with your ITPS. It should cut power after about 50sec. total. I am working on code to reprogram the ITPS for longer delays so PM me if you are interested and I'll post it to the forum and can reprogram your chip for you when I am done.

**cyber** · 08-17-2004, 01:57 PM

Originally Posted by brooksware2000

From your description, I don't see any problems with your ITPS. It should cut power after about 50sec. total.

Originally Posted by cyber256

Then after playing with the GPS I turn my car off. The computer INSTANTLY loses power and turns off. I was under the impression that the computer was supposed to still get power for a couple seconds while gracefully turning off.

The ITPS not supplying power after losing the 12v switched is one of the problems. Is it possible that if my battery is ****ty enough that without the alternator it isn't producing a full 12v?

**mauri** · 08-18-2004, 03:28 PM

Originally Posted by cyber

The ITPS not supplying power after losing the 12v switched is one of the problems. Is it possible that if my battery is ****ty enough that without the alternator it isn't producing a full 12v?

L' ITPS succeeds in giving in exit 12V/5A max Alone if in his/her entrance it has At least 13,4V, otherwise the regulator on board of the ITPS works in passive.
To power on automotive you Have to have at least 13,8/14V and if and' everything ok and colleagues the ITPS with that tension you will see that in Out you will have 12V stabilized.
Always that am not defective!

Bye
Mauri

**Confused** · 08-19-2004, 04:30 AM

All the "problems" you are experiencing with the ITPS are design flaws of the ITPS.

1. Doesn't survive cranking.
- Nope, the regulator on the ITPS requires at least 13.3V in to give 12V out, and your voltage drops to ~8-11V when cranking.

2. Turns off straight away on accessory off.
- Are you SURE you haven't got the switched and permanent round the wrong way. Check this too, but you still probably won't survive cranks due to #1.

I have used an inverter, a Morex DC-DC + ITPS, Opus, and Morex DC-DC + Carnetix regulator, and the only ones that worked properly were the Opus and the Carnetix. This is because they have regulators that can accept wider input voltages, and still give out 12V power.

I would suggest scrapping the ITPS and getting yourself a Carnetix regulator, it will do exactly what your ITPS should do, only it does actually do it.

Garry