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don't worry about your english, it is fine - if something is not clear, we can ask you again...
it seems that PIE is connected to the system correctly, and you need just the video to be put out to the front monitor. My previous write-ups, that you mention, refer to a factory TV tuner, that supports factory rear view camera.
I am not familiar with PIE, but here is what you probably need - a signal that tells the PIE that the car is in reverse gear (hence the reverse lights), and the power for the camera to actually operate.
I would suggest that you supply your camera with permanent source of ignition hot power by using a relay, in order to avoid overtaxing the circuitry - find a wire in the wire loom that has +12 VDC, and the voltage goes to the +13 or +14 VDC when the engine is running. Be careful, there are many wires that carry a signal, and not power. Ground wires are usually brown in color, and the power ones are yellow or yellow with a stripe... the colors in your country might be different...
Once you find a power wire that is switched with ignition, use a small, tiny relay and tap the coil of the relay into that power. then draw the battery power directly into the camera through that relay - by doing this, you avoid placing too much electrical stress on the power wire that you tapped the relay to.
This should resolve the power issue for the camera - it will be on everytime that the ignition is on.
Now you need a signal that will tell the navigation computer to switch from regular screen to the reverse camera. Naturally, the reverse lights are the simplest point to get that signal but, here lies a problem.
In BMW, the electric power that is supplied to the reverse light is not plain +12 VDC to ignite the light bulb. That power is computer regulated (LCM module), and it is a Pulse Modulated Wave (PMW), meanning, that the power is applied in a very quick succession of high and low voltages - the computer monitors the circuitry of the line and will report any abnormalities. This is exactly what is happening in your case, when you introduce additional load to that circuit, the computer thinks that there is a trouble online. If you wish to use the reverse lights for the signal source for rear camera, use another relay - you will need to find a relay with a slow response time, so the rapid changing of the voltage on the reverse lights would not result in flickering of the image on the screen.
If you car is equipped with a PDC module, there is another option to wire the reverse signal.
do you have PDC in your car?
Last edited by TerminatorX5; 08-19-2012 at 01:39 PM.
Reason: spelling
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