Nav+ problems (RNS-D)

carrotchomper · #1 4th September 2009, 10:44 AM

Folks,

This is very annoying. The Nav+ unit in my PF D2 ('98) works perfectly... Apart from the Nav

When I bought the car down in Somerset, the unit was locked, as the battery had been flat. Finally found the code, and tried the Nav- It worked fine, showed current location correctly and when set to navigate to Bristol showed the correct-ish route and distance.

I obviously didn't use it then as I know the way! Since then I have needed to use it a couple of times, and the GPS constantly thinks it is somewhere near Poole. It will accept a destination, but obviously won't navigate there- On the "Lat/Lon" display it constantly shows what I believe is a default...

...This is doubly annoying because my little Garmin portable Nav unit has ceased to pick up satellites for some unknown reason

It has the most up-to-date Nav CD in it (2005?) which I think you can get for mine...

Help!

IT · #2 4th September 2009, 11:54 AM

2007 is the most recent disc you can get.....

If it doesn't know where it is, then it either has a GPS aerial fault, or the connection that supplies the speed pulses is faulty.

I favour the former as the most likely candidate, and one of the Sat Nav menus will confirm how many satelites are available - If this reads zero then almost certainly the GPS aerial. Cheap replacements ones can be bought for around a tenner, and if nothing else you can plug it in directly to the back of the unit to prove whether its faulty.

The aerial on the boot lid has about a meter of length on it, it connects to an extension that runs the full length of the car, and it connects behind the trim behind the Cd changer on the left hand side of the boot.

If you do get an aftermarket aerial, and it works in the back of the head unit, plug it into the end of the extension at the boot side and then eliminate the 5m length of coax that runs the lenght of the car.

If that also works, then you're looking at a faulty GPS aerial on the boot, which you could replace, or just stick the £10 one on the dashboard tucked in the corner out of the way....

Either way, im sure it wont be difficult to fix, and its almost certainly not a fault with the head unit...

carrotchomper · #3 6th September 2009, 05:35 PM

Quote:

Originally Posted by Ian@A8Parts

Useful stuff

Ian,

Thanks for another informative reply

I was thinking along the lines of the aerial myself. As far as I can remember the display does say "0" satellites.

I like the idea of tucking an aftermarket one away somewhere- The OEM one is colour coded!

Are they a universal fitment- IE what shape/type of connector do I need?

PsYcHe · #4 6th September 2009, 05:47 PM

Figure11 has done a chunk of preliminary work on this.

Given the size of the unit on the boot and the size of a modern GPS mouse, you should be able to sneak the guts into the original space, or even at the bottom of the windscreen if you don't have the athermic glass and then just run the cable along. Can't remember which connector it is, but you can get adapters pretty cheap on t'interwebs.

IT · #5 6th September 2009, 08:50 PM

Quote:

Originally Posted by carrotchomper

Ian,

Thanks for another informative reply

I was thinking along the lines of the aerial myself. As far as I can remember the display does say "0" satellites.

I like the idea of tucking an aftermarket one away somewhere- The OEM one is colour coded!

Are they a universal fitment- IE what shape/type of connector do I need?

Check this item out:

http://cgi.ebay.co.uk/GPS-Antenna-SM...d=p3286.c0.m14

Although I'm 99% sure we have a brand new one in stock, and could do it at a similar price....

carrotchomper · #6 25th April 2010, 10:24 AM

Thanks all, but I'm STILL having problems... Bought an aftermarket aerial from the good folks at A8parts which turned out to be the wrong size, have a new one now (Ta muchly!) and it still doesn't want to work... Plugged it directly into the back of the Nav+ unit and have variously dangled the antenna on the roof, outside the car and in the windscreen, and still doesn't pick up satellites.

Since I've plugged it in, the available satellites display has gone from around 25/27 to 30, however at best it only shows 1 satellite as "receiving"- Which obviously won't work..

Help! Should I plug it in at the boot instead?

PS- It's actually a RNS-C unit

#7 27th April 2010, 03:58 PM

My sat nav seems to have developed the same fault. I tried to use it today and it can't get a fix on my location. Had a look at the GPS Viewer menu and it says Available 30 Recieve 0.

Everything worked fine last time i used it a couple of weeks ago.

What connections are there from the receiver? Is there a connection within the boot lid which might have worked loose or does the cable run continuously to the Nav unit?

IT · #8 27th April 2010, 08:25 PM

Quote:

Originally Posted by carrotchomper

Thanks all, but I'm STILL having problems... Bought an aftermarket aerial from the good folks at A8parts which turned out to be the wrong size, have a new one now (Ta muchly!) and it still doesn't want to work... Plugged it directly into the back of the Nav+ unit and have variously dangled the antenna on the roof, outside the car and in the windscreen, and still doesn't pick up satellites.

Since I've plugged it in, the available satellites display has gone from around 25/27 to 30, however at best it only shows 1 satellite as "receiving"- Which obviously won't work..

Help! Should I plug it in at the boot instead?

PS- It's actually a RNS-C unit

Connecting it further away cant possibly help.... I have seen a few units now where the aerial connection on the rear seems to have failed, ie the head unit is duff without some stripping down and resolding of (what I suspect is) a dry solder joint....

If you have got the right aerial (the SMB connector clicks on quite re-assuringly, you'd know if it was wrong) plugged directly into the rear of the unit, and it is in good line of sight of satelites (pop it on the roof for the test, not inside the car, and dont be in a built up area if possible), and you get 0 satelites received the only logical answer is for the Nav unit to be faulty.....

Edit - Given that GPS technology is 4 dimensional, and has to fix 'time' before it can get a fix on position, it can take a good few minutes to get a fix. Dont be spoilt by little handheld devices that get a fix in half a minute, you need to show some real patience here and I'd give it a good 5 mins myself before I wrote it off...

tonupkid · #9 5th September 2009, 12:11 PM

...This is doubly annoying because my little Garmin portable Nav unit has ceased to pick up satellites for some unknown reason

[/quote]

My Garmin has the same problem. I think this is caused by the S8's slightly mirrored glass making the interior of the car somewhat impervious to radio signals. Not enough to block mobiles, but enough the leave my Garmin struggling.
Sounds like your glass may be mirrored too.
A simple test is to try your Garmin outside, then inside the car

carrotchomper · #10 6th September 2009, 05:32 PM

Quote:

Originally Posted by tonupkid

.
My Garmin has the same problem. I think this is caused by the S8's slightly mirrored glass making the interior of the car somewhat impervious to radio signals. Not enough to block mobiles, but enough the leave my Garmin struggling.
Sounds like your glass may be mirrored too.
A simple test is to try your Garmin outside, then inside the car

Thanks- But it's done it in other cars, and outside the car too... Deeed I think! It is rather old now in any case.