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Hey all,
I am wondering if there is any CAN Bus electrical geniuses out their in RennList land that can help me with some knowledge.
I am looking at the center console setup for a 991, and wondering how the buttons are triggered.
Excuse my ignorance to this subject, but that is why I am asking those here in hope to find someone who can help.
What I am wondering is if there is a way to wire in a piggyback switch to the CAN system? (basically creating a second point to activate the specific button)
*** Given if there is no way to create a secondary activation point, then I would be fine with just being able to know how to connect something to activate the CAN Bus button from a different location (eliminating the use of the original button all together).
Attached are pictures of the center console and its internals. In the picture of the center console opened up, the contacts on the green electronics board (on the left) and the black rubber/silicone matting (on the left) match up accordingly.
Any constructive help would be greatly appreciated.
Thanks!
are there just 3 or 4 wires out of that module or like 16?
if there are a whole bunch of wires (like 2 * button count) then it's a simple circuit being completed against a module elsewhere in the car. programming that module to understand which two wires is supposed to trigger what is how the magic happens. if that's the case, just short the correct two wires together (verify that's what the button is doing, first!) and you're set.
if there are just a few wires, then it is indeed a CANBUS (or whatever more modern system than CAN, I forget the name or if the 991 uses it), and wiring a secondary switch there will require sending a specific signal over the BUS, which involves putting some kind of microcontroller in place. You can do this with real cheap SOC hardware, like a knockoff of an arduino nano or some such, as a lot of them natively support CANBUS. wire that up to a switch and blast out the applicable message on the network and you're set.
are there just 3 or 4 wires out of that module or like 16?
if there are a whole bunch of wires (like 2 * button count) then it's a simple circuit being completed against a module elsewhere in the car. programming that module to understand which two wires is supposed to trigger what is how the magic happens. if that's the case, just short the correct two wires together (verify that's what the button is doing, first!) and you're set.
if there are just a few wires, then it is indeed a CANBUS (or whatever more modern system than CAN, I forget the name or if the 991 uses it), and wiring a secondary switch there will require sending a specific signal over the BUS, which involves putting some kind of microcontroller in place. You can do this with real cheap SOC hardware, like a knockoff of an arduino nano or some such, as a lot of them natively support CANBUS. wire that up to a switch and blast out the applicable message on the network and you're set.
Hi asellus,
Thanks for the response. To answer your questions...
The center console has just basically the electronics green board (everything else is just a contact, no wiring or anything to them). The green board has a 3 prong male connector underneath which will connect to the wiring in the center console area.
So based on what you are stating, there isnt a way to activate the switch by say connecting the center of the gold bullseye with the outer ring of the gold bullseye?
I would need the soc hard you mentioned?
Hi asellus,
Thanks for the response. To answer your questions...
The center console has just basically the electronics green board (everything else is just a contact, no wiring or anything to them). The green board has a 3 prong male connector underneath which will connect to the wiring in the center console area.
So based on what you are stating, there isnt a way to activate the switch by say connecting the center of the gold bullseye with the outer ring of the gold bullseye?
I would need the soc hard you mentioned?
Yeah with only 3 pins coming out to go to the car, that whole thing is a module. +12v, GND, and CAN (or LIN, is it?) signal. Usually it's CAN+ and CAN- but I'll admit I haven't futzed with this stuff too much.
Connecting the center to the outer ring of each bullseye is how that board functions, yes. The module itself interprets what button was pressed, what that buttons means per the coding, and sends the appropriate signal across the bus. The buttons smoosh down onto them to connect them together. You could solder on some wires to those two traces and hook that up to an external switch, but I'd make sure your soldering skills and equipment is up to snuff before trying that out. Some real thin wire might be needed in order to close everything up cleanly, too.
Noah Fect, do you think I could get the button to turn on by the method I mentioned above?
(connecting a wire to the outer ring on one side, and a switch on the other. and then from the switch to the inner ring.... then opening the switch circuit will technically connect the two parts)
Thanks for the help
Yeah with only 3 pins coming out to go to the car, that whole thing is a module. +12v, GND, and CAN (or LIN, is it?) signal. Usually it's CAN+ and CAN- but I'll admit I haven't futzed with this stuff too much.
Connecting the center to the outer ring of each bullseye is how that board functions, yes. The module itself interprets what button was pressed, what that buttons means per the coding, and sends the appropriate signal across the bus. The buttons smoosh down onto them to connect them together. You could solder on some wires to those two traces and hook that up to an external switch, but I'd make sure your soldering skills and equipment is up to snuff before trying that out. Some real thin wire might be needed in order to close everything up cleanly, too.
Asellus, thats cool to know that it shoooooooould work. I guess I might want to look into further.
I guess the other thing I wonder is if the wire length and thickness will effect the amount of volts needed. I mean as it sits right now, the connection is obvious extremely short. But if the connection distance is extended to like 8 feet (4 feet in to the switch and then 4 feet return), would there be enough to activate the button on the electronics board?
Thanks for all the help
Noah Fect, do you think I could get the button to turn on by the method I mentioned above?
(connecting a wire to the outer ring on one side, and a switch on the other. and then from the switch to the inner ring.... then opening the switch circuit will technically connect the two parts)
Thanks for the help
Sure. anything that completes the circuit will do the trick. I'd suggest twisting the wires together to discourage false triggering due to EMI, though. Also be aware that static discharge can damage components at levels too low to perceive as a shock.
Make sure that something like the T-Design module (which is similar to Zapta's github project) doesn't already do what you need.
Sure. anything that completes the circuit will do the trick. I'd suggest twisting the wires together to discourage false triggering due to EMI, though. Also be aware that static discharge can damage components at levels too low to perceive as a shock.
Make sure that something like the T-Design module (which is similar to Zapta's github project) doesn't already do what you need.
Could you point me the direction of the T-design module or Zapta's github project?
I havent heard of these before
Thanks
If I understand you correctly you want to use one of the spare button locations in the center console to do some action.
This would require reprogramming the actual central console with custom software which I do not believe anyone has done.
You can connect to the bus to send messages as well but you'll either have to hacksaw that center console or place the button somewhere else.
If I understand you correctly you want to use one of the spare button locations in the center console to do some action.
This would require reprogramming the actual central console with custom software which I do not believe anyone has done.
You can connect to the bus to send messages as well but you'll either have to hacksaw that center console or place the button somewhere else.
Actually no.
All I am trying to do is lets say extend the button's location.
Basically it does exactly what it is suppose to do, but instead of it being activated at the OEM location.... i would just have it activate in another location
The use of wire will be to extend the location, and a click down/ click up button will be to do what the stock button does
Ahh ok, yes you can solder yourself to the console or add Lin or canbus module that replicates the message you'd like to send.
CAN is easier if that function is requested via CAN as you just jump on the bus anywhere in the line.
Ahh ok, yes you can solder yourself to the console or add Lin or canbus module that replicates the message you'd like to send.
CAN is easier if that function is requested via CAN as you just jump on the bus anywhere in the line.
VII7, does it have to be a module that is soldered? Literally all I am hoping to do is solder 1 wire to the outer ring, 1 wire to the inner circle. and then use a click on/ click off switch to connect the two (as it appears the oem console button does the same thing by just pressing down a circular metal piece that connects the outer ring and inner circle.
in basic house electrical terms, all i am attempting to do is try to is move a wall switch from one spot to another spot further away
do you think this is possible?
and easily done?
No, if you are going to solder into the central console it's just a contact. The central console will do the communication.
If you did not want to solder into it then you would need a canbus emulator module.
01-29-2023, 11:36 AM
Electrical Tech questions about CAN BUs
