Yes I've done the step where you press the menu button and you get to see all the diffrent settings. All I know is that my GPS finds sattellites, up to 8, and It makes some values change over time!?! The marker on the screen finds its way about but almost always misses by 20 metres when turning. Must be the wheelsensors that need fixing! Anyone have a clue as to how i should go about it?

Ok didn't see "Trapdoors" thread, just wanted to ask if you know if this applies to cars which used the special harness kit or in general retrofittnings? I know for a fact that my harness came off a salvaged car from a scrapheap/yard so I know that its OEM. But I'll try to remove and transposition the pins. Thanks for the help guys!

What GPS HDOP and PDOP do you get? A good GPS fix will have an HDOP of <1.5, mine is mostly between 1.2 and 1.8
An HDPO of over 5 is a pretty poor position.
HDOP = horizontal dilution of position, PDOP = positional dilution of precision. The lower the HDOP, the more accurate the position calculation from the GPS.

For the Mk4, the left-front speed sensor is connected to pin 10 on the nav. Don't blindly play with the loom, you should confirm that it is wired correctly as per the instructions.

From the PUMA case that my dealer raised, it was both Factory fit and Retrofit harnesses that were faulty. It was a dud batch from the cable manufacturer. Don't know how many were made that way, but the factory looms were replaced before the retrofit kits. BMW dealers were supposed to have been given instructions with the retrofits to check/change pin 10 & 11. Needless to say, this didn't happen much.

So, in summary, just because it came off a scrapped car which had factory fit nav doesn't mean to say that it has a good loom. Chances are it has an incorrectly wired loom.

For a GPS-only system, DOP's are important as they will possibly reduce resolution, but the BMW system is supposed to improve this with both Gyro and Wheel Sensors which compensate for loss of GPS signal and poor DOP's (which WILL go up & down depending on the number of visible birds and where they are in relation to each other).

It used to be MUCH worse when the US government were running Selective Availability - ie they would randomly degrade the positional accuracy deliberately for the civilian GPS service.....

Jochen --> I don't remeber the exact order of things but I had values like (in order) 1) ~3 2) ~2 3) ~2 = HDOP/VDOP/PDOP (don't remeber the order as said)
And when driving around the "direction of travel" shows reverse! And gives me negative values! I'll try to do as Trapdoor said, that is interchange the pins. Don't yet know on what plug I should change the pins on? Is it the one connected to the MK4 nav itself, the blue one, or?

Read this http://www.xoutpost.com/articles/all-...formation.html several times!

It is the maroon coloured plug in the back of the Mk4..... check whether there is a connection in PIN10 and what the colours are.....

As I say, all the info is in the info in the link.

Feel a bit thick! Thanks "Trapdoor" I'll look into it straight away. Cheers!

>> And when driving around the "direction of travel" shows reverse!

Check the reverse signal connection to pin 1 of the purple connector.

It should be >5V when in reverse, and 0V when in all other gears.
If wired to the light control module (correct location) the wire will have about +6V when in reverse.
If wired to reverse lights (happens on some retro-fits) it will have +12V when in reverse.

Sounds like this wire might be +12V all the time.
Remove the pin from the connector to temporarily disconnect this wire then check performance of nav.

This wire is used to tell the nav you are going backwards, so disconnecting it produces the same results as travelling forwards.

If you have 12V on this wire all the time, check where it is wired to, maybe the LKM is faulty, or maybe the wire is conencted to the wron place on the LKM.

Jochen

"Sounds like this wire might be +12V all the time"

-Then It shouldn't show the direction of travel as being forward when going backwards! Maybe there's a pin/plug that's been put in the wrong socket. I'll still unplug pin 1 and change pin 10 w/ pin 11. Cheers!