Saab 93 OEM installation (Now running Android)
Since I saw the first factory colour screen in a car I always liked to expand the functionality of this display, mantaining the factory looking of the dash. That is my main goal. I think factory screens have the perfect resolution/quality for the purpose they are designed for.
My car is a MY05 Saab 93 SS. It comes with the ICM3 colour display. The first problem was it does not have any external video input. So I had to disassemble the whole unit and spend some weeks of reverse engineering the LCD. Internally, it was like some other screens I have seen, analog RGB with NTSC timings. Time to design a video switch circuit.
But I wanted to convert into touch screen too, and, why not, connect to the CAN network and catch events like reverse gear insertion (intended for automatic reverse camera switching) or button pushing (manual video switching using factory buttons). The CAN network (GM SWCAN) takes me another couple of weeks of decoding commands. How to sniff the SWCAN here
The circuit. It has the USB touch panel controller integrated:
The adapter integrated inside the screen ecu:
The touch panel installation
And the external connection:
Testing the results. PC connected through the VGA connection of the converter and an special driver:
Running emulated Windows Mobile in XP:
Note: the display is 400x234 pixel res.
The next step was the reverse camera connection. But most of the cameras are CVBS video signal (composite). So I had to design a CVBS (RCA) to RGB video converter. I know there are some converters of this kind in the market, but I want to make it myself, according with my personal requirements. After a few "fights" with old analog TV ICs, I decided to go into fully digital conversion. The results were worth it.
The converter has two CVBS (RCA) inputs and one RGB (VGA). One RCA is reserved for reverse camera, the other one is generic. The VGA input is intended for connecting the Carpc.
The installation diagram I have planned:
Here is the converter internals:
Drilling the trunk:
Rear camera installed:
Routing the camera wires through the trunk lid:
Video converter instaled in the trunk:
And the final result: