Hello Guys,

I went to the car audio shop and asked about the VIM for W204. He told me that it is possible to have VIM but then I have to turn of the navigation because ones the GPS picks up moving signals from the car it will still shut down VIM.
Conclusion is VIM Or Navi. Both available but not at the same time?

Is this true?

 

i don't think so. never heard such.
take a look at www.midcityengineering.com

 

Well that makes sense if you select Navi the DVD will not play You may still get audio. But if you mean that you have DVD selected and start to move (with VIM) then the Navi will take over automaticaly, I don't think so.

 

oh. i guess i understood wrong. after reading Ron_Jr's post, it makes sense.

 

after some research, this comand system recognize whether the car is in motion or not by GPS.
so for VIM module, giving false info(disabling GPS antenna) while car is driving, thus making VIM possible.

this will cause erratic behavior once the driver selects GPS after using VIM. i believe VaderSS had this issue before, but that post has been deleted for some reason.

 

Once you disable VIM, your GPS signal should return in about a minute or so.

 

Yes. It makes total sense now. I guess it takes about a min to re-sync GPS. Makes me thinking what if I disable GPS from engineering menu and drive? Getting interesting.

 

Damn... I like the way you think! If you figure it out you'll be putting someone out of business!

Unfortunately I don't think there is an easy "one button" operation to turn on/off your GPS. You'd have to essentially pull off to the side, and then go into your engineering menu to re/enable GPS.

 

i'll test this one the way to work tomorrow morning.

couple things to take in consideration,
1. disabling GPS from engineering menu doesn't really disable it. -> further testing will be disconnect GPS antenna physically from COMAND.
2. COMAND system might have other ways of checking whether the car is driving or not. in this case, i'm screwed~~!!

hopefully i'm not ruining anyone's business.
i'm doing this because I want to KNOW how it works rather just using it. And posting on forum to discuss about it. Isn't it whole point of having forum?

 

nah.. if only it were that easy... on the W204 the video disable is keyed into three things: GPS signal, gearshift position, and wheel speed sensor. all three have to register that the car is sitting still or the video output is disabled. on mercedes, all the information runs over the CAN network. other vehicles have hard wired signals on individual wires and a common hack was to install a switch that would disconnect those wires (e.g. parking brake and speed sense signal are still common on some lexus models) but with mercedes there is no easy way. What the VIM module is actually doing is taking all the data over the network and then selectively changing certain data parameters to make only the radio think that the vehicle is sitting still when in fact it is moving. At the same time it also has to disconnect the GPS antenna when you select vim mode and it has to do all this reliably. there is actually about 8000 lines of code involved in making all this happen.

Incidentally I am the same way.. I like to look into how things work and figure them out and got started years ago with mercedes because these cars are so advanced that nobody wanted to mess with them. little did i realize how much there was to learn (and its alot....)

 

I want to know what you all find out. However, how difficult is the midcity install?

 

As far as DIY, I would rate it an intermediate.

Time, patience and thick skin will help you prevail

 

yes. i was hoping there is only GPS checking and possibly gear selector check. But boy... there are 3??!! Darn it.... I guess there will be no more testing on VIM. hahahaha.
Thank you for your support.