Strange order configuration there mate,
I did not think that you could get tv withouth nav
Sorry that i cant help you with your question

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X5 4,4i-06 Current
330Ci Cab-03 2007-2008
MB E55 AMG-03 2006-2007
Z3 2,8 Roadster-98 2006-2007
X3 2,0d-05 2005-2006
320d-99 1999-2005

Is your TV functonal?
The cable that is installed is probably useful only for your TV.
For NAVI, you 'll probably need not only the special cable (different from the TV one) but also a GPS antenna (I don't know where it is installed in an M3).
This antenna is installed on the little back spoiler, at the backend of an X5.
After installation, a programming procedure with suitable equipment should be performed from a dealer.

From what I hear you will need to install a different wire harness as the TV harness in your car doesn't support navigation. The harness runs from the screen upfront all the way to the trunk. You will need to find one that supports both Nav and TV and then you should be able to add a nav computer and GPS antenna.

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95 e38 740iL, 01 facelift, 6000k HID,Alpina front air dam,Alpina 20" Softlines,HR Drop springs,Germany front plate,CCFL Angel Eyes,Full leather/wood 750iL int,16:9 Nav Retro,MK4,DVD video interface,20% tint all around.
99 e38 740iL, Style 94 wheels,Nav retro,16:9,RR MK3
00 Cadillac DeVille, blacked out on chrome vogue wheels
02 Harley Davidson softail

Yes, you can do what you want to do.

Leave the blue plug in the TV, but add the loom that connects the nav blue plug to the TV tuner white plug. Look on ebay for these, one from an E39 will do just fine.

Then you need to cable the purple plug, as this has the dead reckoning signals (speed pulse, direction indication)

And of course a GPS antenna.

Once cabled it will work, but you should get the system coded by a dealer so that the car properly knows that it has navigation fitted.

Thanks very much, exactly what I was after hearing!! I don;t suppose you know the part number for the loom from the E39?

Terry

Don't know the part number, but here it is on ebay for sale:
http://cgi.ebay.de/Kabelbaum-Navi-fu...QQcmdZViewItem

This plugs into nav (purple + blue) and into video module (white)

The longer black & white plugs then need to be joined to power+ground+speed pulse, all available at the radio module behind the video module

You then only need to run one wire to the reverse light wire on the right hand wheel arch to pick up the reverse signal.

What is the reverse signal for?

Rear camera?

In dead-deckoning mode, and to verify the GPS signal, the nav uses the inbuilt gyro compass, and the external wheel pulses to update the current position.

Wheel pulses however do not indicate if the vehicle is moving forwards or backwards, they only indicate speed.

So the nav requires the reverse gear signal to determine if the car is moving forwards or backwards.

Vital for correct position calculation under condiitons of bad GPS signals, eg: in car parking buildings, tunnels, densly built up areas, or even days of heavy rain and dense fog when the GPS signal gets weak (like I had last Friday - my GPS strugggled and calculated huge position and speed errors, at times I was doing 250kmph - because my GPS had no dead reckoning capability, therefore could only use GPS signals, which sometimes have large errors)