MK4 navigation computer calibration
 

hello,I upgrated my mk2 to mk4 computer but it working not as it should.If i am already in round about it show 40m to go.Would like to ask if is possible to calibrate it or some how ajust it.Thanks

To calibrate the mk4.

Get onto a motorway and travel at a constant 60mph for 15 - 20 minutes and this should sync the speed sensor to the cars GPS signal.

Remember no speeding up or slowing down, keep the speed constant, (set the cruse control).

Thanks i will try this.

I tryed this still the same.Anyone knows other methods of computer calibration.

Remember a Mk4 can take a week to 2 weeks to adapt from one vehicle to another, depending on types of roads driven and how often you drive.

Be patient, and report back in 2 weeks time if the problem still exists

Thanks, i will report back in 2 weeks.

Before go, check in the Service Menu to ensure that GPS reception is working OK. Here is a post that explains how to get into the Service Menu and what to look for: http://www.xoutpost.com/607084-post2.html.

Thanks i will try this tomorrow and let you know.

I checked these settings and it seems right as on that description nothing that goes over or under the limit.on the sceen is 4-1-00.I've had this computer for around 2 weeks.

Was your "GPS Status" "position known," and did the longitude and latitude look correct?

Yes position known and i think longitude and latitude ok.

have been driving with it for over month with it gps still behing the car for about 30m.

are you sure, that what your screen displays, deviates among 30m from reality? in my case, the difference is about 5 to 10m and it recalibrates itself, when i turn left or right on a crossroad.

you wrote, that you upgradet from MKII to MKIV. perhaps the gps-reciever is "too old" and it recieves only a fixed amount of signals.
the accuracy depends on your environment, so it should be less, when you're riding downtown, because of the skyscrapers, or through a tunnel.

There is technical document over this in WDS, an if I remember correctly it suggests to make circles (in a square or round about) in order to adjust your GPS. Try small 3-4 circles in the same spot, then in opposite direction.
I hope this would fix your problem.

Are you getting 'Wheel Speed' indications in the diagnostic screen? If not, then this will show your position as being out when compared to reality.

Had this issue in my E46 where I was always ahead of the map pointer by 20 oe 30 meters - the dealer had used the correct full retrofit kit when they installed my nav, but some of the looms were faulty from the factory and had the wheel speed sensor wire in the wrong connector. As soon as it was put into the correct socket, the accuracy was spot on. This speed signal, plus the input from the accelerometers is used to 'correct' any accuracy issues with the GPS and to keep the map updating correctly when you are out of GPS coverage such as in a tunnel.

It may be that there is a fault with the speed sensor line, or the loom is bad/faulty/miswired.