Question For Factory Fitted Sat Nav Owners

[dulux72]

Hi there

 

Could someone help me get the correct figures for the factory fitted sat nav.

 

I need to tell the system the number of pulses per revolution and the circumference of the wheel.

 

This info is stored within your installed system and would really help me out.

Don't worry about accessing it as I can talk you to the correct screen to get the info.

 

If you have sat nav as a factory fit please can someone help me with this. :unsure:

[Guest thobbs]

OMG! i thought it was a case of purchasing a SATNAV unit, pulling out the current CD Player, something to do with the GPS ariel lead and possibly a cable which needs to be connected to the speed sensor...

 

Hopefully you will get someone to answer this and I might actually start looking at replacing the CD player for a SATNAV unit, if you don't mind which unit have you got?

 

Thanks,

 

Tim (Only MAYBE installing SATNAV to the wife's Galaxy :unsure: )

[dulux72]

Well let me explain

I had the single disc 6000 RDS Ford Radio

 

To retro fit the Ford Sat Nav you have to do the following;

 

Replace the complete centre fascia and all blanking plates and switches.

YES the fascia needs replacing as the SATNAV is about 20mm bigger than the 6000 RDS

Install a new wiring loom adaptor and GPS ariel (From Ebay)

And connect the speed sensor wire / gala (Purple Wire)

 

Oh and get an up to date copy of the navigation disc

 

I have done all this and it looks great and works BUT because I need to set the pulses per rotation and wheel circumference the maps are currently about 300 metres behind my actual position.

 

Hence the request for the info from someone with a factory fit system.

[johnb80]

These system SHOULD calibrate themselves, the pulses per distance will vary as tyre wear, pressures differ etc. The system knows it's position on a regular basis and can therefore reset it's own distance / pulse relationship. My clarion system took about 20 minutes to get it sorted, go for a drive !

 

Regards - John

[Guest j_mchattie]

If its 300m behind ALL the time, then the circumfrence is correct. I havent seen what your looking at, but it sounds like you just need to aquire more satelittes.

 

Ive never heard of a wheel circumference being asked for before.

[jkspoff]

Its GPS, therefore your postion will be calculated from satelite positions, not from the amount of RPM on the wheels. The wheel measurements are only for calculating the time of arrival in relation to your current speed.i.e. sat in traffic jams etc ;)

[Guest j_mchattie]

Even the ETA can be done via the satelittes - its just distance over speed. How could a GPS system account for corners and stuff with differential? Both wheels go different speeds.

 

I agree with JOHNB80, drive it around and give it a chance.

[johnb80]

Its GPS, therefore your postion will be calculated from satelite positions, not from the amount of RPM on the wheels. The wheel measurements are only for calculating the time of arrival in relation to your current speed.i.e. sat in traffic jams etc ;)

Thats not correct. The speed pulse is used to make the map move etc, the satellites are used for reference and updating a position every 30 to 50 metres. My Clarion system as with most other SATNAV's (Not the PDA/Phone types) have a built in compass and gyro to keep the accuracy good. If running on satellites alone it will only update about every 30 to 40 metres dependent on the number of satellites being received. On my van I had a VDO SatNav just after leaving home (Gainsborough, Lincs) the antenna for the satnav failed. My journey continued with amazing accuracy all the way to Brighton, on arrival it was out by about 130 metres.

 

Regards - John

[dulux72]

OK here's a further update

 

The position IE: LONG & LAT is correct

I have checked this with another device. :huh:

 

BUT its wrong on the map. As I have said its about 300 metres out.

 

I have taken Johnb80 advice and driven for about 40 mins and the screen updates etc but the position shown on the screen is wrong.

 

Could the CD containing the maps be wrong ??? :(

 

Has no one got a factory fitted system ???? ;)

[_dg]

Seems like a lot of phaffing about.

 

Is the built in system actually any better than an after-market one?

 

I use TomTom on a PDA and also a on phone, and accuracy and redrawing of the maps is spot on

[Masked Marauder]

Seems like a lot of phaffing about.

 

Is the built in system actually any better than an after-market one?

 

I use TomTom on a PDA and also a on phone, and accuracy and redrawing of the maps is spot on

Aye, me too, and nothing connected to my wheels. It is also surprisingly good at predicting where you are if the satellite signal is lost in a tunnel etc.

 

I did a 300 mile trip the other weekend and the ETA was spot on too.

[Dally]

Could the CD containing the maps be wrong ??? :huh:

 

Has no one got a factory fitted system ???? ;)

Hello Dulux72.

 

I have factory fit satnav and it's pretty much spot on. How can I help?

[dulux72]

Thanks Dally

 

I have sent you an email explaining how to get to the screen in which the info is shown.

 

Many many thanks

[Masked Marauder]

I hope you get it sorted, nothing is worse than having gone to the expense of getting something only to find that you can't get to work properly and do what it should.

 

Talking of which, did I mention my other half, Tiffany........

[dulux72]

LOL

 

I take it she doesn't read the forum.

 

Hopefully with dally's help it'll be sorted.........

[Masked Marauder]

No, she is too busy driving the Alhambra.....

[dulux72]

Dally

 

Did you manage to understand my email and access the info ?? :huh:

[Dally]

dulux72

 

Sorry I've been out - I got your email and will try it later today.

[Dally]

dulux72

 

The readings are: -

 

Tyre circumference - 1978

pulses per rev. - 48

 

Let me know if this helps.

BTW - I am running on 215/55 16" rubber.

 

Regards

 

Dally

[dulux72]

:huh: WHAT A STAR :D

 

Thanks exactly the info I needed

 

Will give it a try and let you know

Many thanks