Sat Nav..............again!

[Starensis]

Can anyone tell me if when you acquire a second hand sat nav unit ( CD-ROM), if it has to be configured to vehicle VIN by dealer?

Bought one last week & doesn't pick up satellites! North & West readings are all reading Zero & will not determine route.

Just wondering if this is the case or you have to drive it around for a while to allow it to pick up signals?

Any ideas would be appreciated.

Thanks in advance.

<_<

[PeterL]

Hi Starensis,

If you've got as far as getting the lat and long display, I doubt if its trying to lock you out for lack of VIN or security code. If it was going to do that, surely it would do it at startup - not just lock out just the GPS reception.

Other than that, I would check its antenna connection. It sounds like all other critical connections are OK.

GPS antenna's are almost always active devices. There is an amplifier built in to the antenna its self. Power is supplied up the coax. Do you know if the antenna in the car your testing with works?

If a GPS receiver has been switched off a long time (weeks or months), it can take longer to aquire a signal. That was the case for early technology at least, but things may have improved. It would be worth leaving it somewhere it can see plenty of sky for ten minutes. I'd have thought that would be long enough.

Does anyone know where abouts the GPS antenna is on the different cars? I haven't found where they've hidden it on my Avensis yet.

[steveo67]

Aquisition of position relies on the unit knowing where all the satellites should be. All the satellites downlink this data to the GPS unit but it can take a while depending on the reception conditiions. |If you unplug the unit this data is lost and it has to be re-aquired.

However, to use the info the unit needs to have a fair idea of what time of day it is so it can tell which sattelites are likely to be visible at that time. The units clock needs to be set fairly accurately for all this to tie up and a position to be generated. If things have been off for a while the time will have been lost too.

This happened to me recently and it took ages to get going again. In the end I had to set the unit to GMT to regain a positional fix.

Interestingly the position relative to the all zero position seems to update fairly accurately even without the absolute fix. Anyone know if theres an inertial unit fitted somewhere to 'fill in' between GPS updates?

I'm not sure where the antenna is located on an Avensis for sure but I've seen reference to it being behind the dash instrument cluster somewhere (but not the black nipple near the window!) Does anyone have the install instructions for the system?

Hope this helps.

[NickE]

The reason you have to set the time before the system can aquire satellite signals is that, without the local time zone being specified, the system thinks it is in Japan, running at Japanese local time. Presumably the time signals decoded from the currently visible satellites are so far removed from the time the system thinks it is, it is ignoring those signals thinking they are errors. If you set the correct local time, the system will have a margin of (time) error within which it will accept a signal as being correct and so the system will aquire the signals.

Hope this makes sense.

Nick

[Eelco]

I also bought a second hand TNS-200.

It was unpowered for at least 3 months. I took the system almost one hour to configure itself to the exact location.

Eelco

[insider]

the antenna on the avensis is on top of the clocks under the dash :hokus-pokus:

[yannick]

I'm not sure where the antenna is located on an Avensis for sure but I've seen reference to it being behind the dash instrument cluster somewhere (but not the black nipple near the window!) Does anyone have the install instructions for the system?

Can anyone tell me what that black nipple is?

[jaxx]

Can anyone tell me what that black nipple is?

perhaps you should see a doctor

sorry off topic............back on track

[flyfisherman]

Hi Starensis,

I too am having dificulties with Satelitte Navigation. My Emmina came with a Toyota Orginal Car Audio 36004 KNT-5180 unit fitted. Within the unit is a sat nav programme run from a CD-Rom disk from Aisin AW Co. Ltd/Zerrin Co Ltd. Tyhe only problem is that it is in Japanese. I have tried to get a UK version but as yet havent been lucky. Do you know if your disc will run on my unit?, if you think it will, where can I get a copy of the disk?

I look forward to hearing from you soon.

Flyfisherman Hertforsdshire.

[HKS_TC_Corolla_GTi]

Hi

Its not all that simple. The Jap Sat Nav systems run with Jap discs and the internal ROM which holds the software to run the system is designed around the Jap discs.

So, you have to do the following;

1) Replace Jap disc with UK disc

2) Replace ROM with EPROM

3) Obtain software from UK Sat Nav system from its ROM and dump to the EPROM in the Jap system.

Your done.....simple isnt it. I can do these but with the costs involved most people dont want to pay.