Lilliput Powering On/Off problem

masch · 05-09-2004, 11:55 AM

Hola

Recently, I made a mod to my lilliput in the TM701L indash housing. I changed the default round wire to a ribbon cable.

http://www.mp3car.com/vbulletin/show...8&postcount=90

Attached is the pic from coyote's post of the default schematic.

Well the problem here is my lilliput keeps going on and off and I havent modded the power switch yet. Maybe I accidentally burnt something I dont know.. but the connector with the ribbon cable doesnt take commands from the slim tiny control board with the infrared receiver anymore.

Now, most of the time, once I apply power, the lilliput automatically turns on.. and I dont know why. Then occasionally, the lilliput turns off automatically. And usually when this starts to happen, it will turn on and off and on and off every 2 seconds or so. This will keep happening until I press the housing's power button and keep holding it. I have this power button soldered to : connect the 150k resistor and the capacitor (+) to this point and take the gnd on this point. The resistor in Remove this resistor is still there. I'm talking about this pic:
http://www.users.skynet.be/media-car...o_power_on.jpg

So I understand that if I keep holding the power button, its like shorting the +5V input thru the 10K resistor to ground. Then of course it wouldnt respond to other commands, but this keeps the screen on.

What I dont understand is, how can the screen turn on and off and on especially if I havent touched any circuitry related to it (at least I dont think so). Its as if something is loose in there thats bypassing the power on button.

1. Could this be because of my soldering of the ribbon cables? Of the 6 wires in the vga signal cable, is there anyone thats telling the screen to shut off/standby?

2. Then again, that doesnt explain why if I keep holding the power button, it doesnt switch off and on and off like it does.. is there someplace I should check?

3. There's also another problem, I dont know if its related. It seems that the slim board with the infrared receiver on it does not seem to work. In fact I dont think its a problem with that slim board, more of a problem with the VGA controller. I tried shorting the tiny tiny pins on the ribbon connector on the VGA controller with no effects.

I dont know what to do now. I can keep the screen on by just simply shorting the power button.. because now I cant even control brightness. (Is there a way to control brightness without depending on the slim board with the infrared receiver?)

If anybody got any idea.. do let me know.