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Custom Made Hvac Sub Audio Display

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36K views 278 replies 17 participants last post by  Marco-mba 
#1 ·
Hi to all Civic owners,

I am running a project to manufacture a custom hvac audio display for my non satnav civic mk8(2010 Model)

I am planing to use a 2.8 Nextion HMI TFT LCD display and a microcontroller board like stm32 or arduino

İdea is simle,
1) connect the microcontroller (stm32 or arduino) to the audio display connector of the car
2) read data coming to the connector pins when a hvac button is pressed or released
3) send a command to the TFT lcd to show an icon or text depending on the value of data

my tft lcd sketch is like below
https://pasteboard.co/IFIEZ8M9.jpg

and this is the pinout diagram of original display
https://www.civinfo.com/wiki/images/5/5b/Nav-audio.jpg

it will be fitted in the sub audio display section of a factory satnav screen and I will use the main satnav screen for something else (reverse cam, video, maybe an external navigation)

I know how to run tft lcd, but I'm not sure which pin to read and how to read tha data (is it analog, digital, voltage, resistance etc)

If I can get some help about it, I will share everytihg I got about this project for everyone willing to try it


Main screen task is already completed( the main screen allways shows navigation interface even if you switch to other menus on the head unit):
https://pasteboard.co/IFIOeMJ.jpg
https://pasteboard.co/IFIOrpn.jpg

sub audio display is the last task
 
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#5 · (Edited)
we have some prgress here

https://pasteboard.co/IGNx4m2.jpg
https://pasteboard.co/IGNxqBC.jpg

1) navigation module is fitted in a original navigation unit enclosure, which will be mounted in the glove box
2) sub audio display is run by a maple mini clone development board,
3) time is adjustable
4) "read serial data and put it on lcd" task to go
 
#7 · (Edited)
this is display connection diagram for non sat nav cars(without navigation with audio)





I need to figure out
a) which pin is the main power for display (probably 5 volts)
b) which pin is the main ground for display
c) which pin is for climate controls data
d) which pin is the power for clock (3.3 or 5 volts probablay - this must be a seperate pin and must suply continious power in order to keep clock uptaded even if the igniton is off)
e) which pin is the ground for clock (may not be necessary)
f) which pin is the trigger for clock adjustment
 
#9 · (Edited)
this is from the wiki (head unit display connector)

D1 BRN Audio-HVAC subdisplay unit (SUB DISP GND)
D2 PNK Audio-HVAC subdisplay unit (SUB DISP 5 V)
D3 ——— Not used
D4 YEL Audio-HVAC subdisplay unit (SUB DISP RST)
D5 PUR Audio-HVAC subdisplay unit (SUB DISP CLOCK)
D6 ORN Audio-HVAC subdisplay unit (SUB DISP DATA)
D7 BLU Audio-HVAC subdisplay unit (SUB DISP CE)
D8 GRY Audio-HVAC subdisplay unit (SUB DISP SHIELD)
D9 PNK Audio-HVAC subdisplay unit (SUB DISP LCD BL-)
D10 LT GRN Audio-HVAC subdisplay unit (SUB DISP LCD BL+)

this does not mean much to me
what is RST
What is DATA
What is CE
What is SHIELD
I believe BL+ and BL- means backlight up and down(I may be wrong)

I tried to power up an original Sub Audio Display on D1 and D2 using a USB power moudle(5 volts) and nothing happened, when I cross changed D1 and D2 I saw a led lighting on pcb
 
#13 · (Edited)
I believe the clock is not part of the car, it is part of the display itself (There must be a RTC real time clock osilator or somethin in it)
we are just sending adjustment commands to set it using steering wheel buttons via the D5 clock pin.
If so the Display must have a continuous power to feed RTC only to keep time updated even if the ignition is off
no matter what, I am using a stm32 board(which has an internal RTC unit with seperate Vbat power input independet off the board) to make my own clock, I plan to use steering wheel commands just to update the clock

as a second case the car may be sending the epoch time to the display as serial data, in this case just a couple of code lines to convert it to human readable format will be easier

I wil make some measurements on every pin to test it soon

I am hopping the the clock is a serial data of epoch time
 
#14 ·
Hi again.

I remember people with double din lost the clock, so they have to buy the connects2 interface. With this interface, the lcd show clock, and besides the date (the date isn't show by the car in origin).
Here I put the specifications of the interface, and tells us how to program the clock and date, so I guess that information is added by the interface and not the screen.
http://www.connects2downloads.co.uk/C2/files/InstallationGuides/CTSHO002_IG_en-GB_v1.pdf

So, I think that clock is in the radio
 
#15 · (Edited)
No, I dont think the clock or date is in the radio, radio is just a bridge to pass the date/time info to the display
for satnav cars there is no date on sub display, but this kit is especially built for non satnav cars which already has date on display, and its main task is to fool the car components to think that commands are coming from oem radio.
On the other hand if you use this kit on a satnav car with an aftermarket head unit and replace the main screen with a non satnav display, boom you have date,
So this means that date and clock is nothing to do with the radio,
eighter date/time is coming from some other component of the car(this does not explain date)
or date/time is reproduced by the connects2
 
#17 ·
I beleive I solved the consant 3.3 volt problem for the RTC Vbat pin on my development board.
I will take constant 12 volts from the main Navigation Display (it has one 12v constant, one 12v accesory/ignition and one ground pin)
using a 12v to 3v convertor I will feed the RTC, so it will always be updated even if the ignition is off
 
#20 ·
Ok! I am stuck at the reading button press/release data from the car (coming over via connects2 adapter)
besides, I have burnt my original non-satnav display
Without any help It seems I can not go any further,
I need data values of each button (analog value or serial data value or digital value etc. I do not know)
 
#21 ·
Hi to all Civic owners,

I am running a project to manufacture a custom hvac audio display for my non satnav civic mk8(2010 Model)

I am planing to use a 2.8 Nextion HMI TFT LCD display and a microcontroller board like stm32 or arduino

İdea is simle,
1) connect the microcontroller (stm32 or arduino) to the audio display connector of the car
2) read data coming to the connector pins when a hvac button is pressed or released
3) send a command to the TFT lcd to show an icon or text depending on the value of data

my tft lcd sketch is like below
Pasteboard - Uploaded Image

and this is the pinout diagram of original display
https://www.civinfo.com/wiki/images/5/5b/Nav-audio.jpg

it will be fitted in the sub audio display section of a factory satnav screen and I will use the main satnav screen for something else (reverse cam, video, maybe an external navigation)

I know how to run tft lcd, but I'm not sure which pin to read and how to read tha data (is it analog, digital, voltage, resistance etc)

If I can get some help about it, I will share everytihg I got about this project for everyone willing to try it


Main screen task is already completed( the main screen allways shows navigation interface even if you switch to other menus on the head unit):
Pasteboard - Uploaded Image
Pasteboard - Uploaded Image

sub audio display is the last task
Not sure if it helps, but here is a link of the datasheet for the chip that drives both Non-SatNav and SatNav HVAC screens: datasheet.pdf
 
#22 ·
Ok here is the news
it seems reading data from display connector is useless,this connector carries special data just fabrication display needs
the main data source is the climate control unit mcu
I have very promising improvment about reading data from there
I am waiting for my iso cable to arrive for begining the test on the car
I beleive I am about to succeed my project very soon
You have to wait until then
 
#275 ·
Hi Mendili2. I'm from South Africa and I own a Honda civic FK2 R18 8th gen.. I have replaced my OEM radio with a double din and now I am struggling to decide between connects2 interface or building something custom.. now I have a FN2 type r Speedo and tacho in the mail and Ill be fitting a K20 in my car in the coming weeks so I want to go full custom on that centre display. we unfortunately never received a Nav version of this car in South Africa so I'll be either reusing my display or fitting a Arduino with a custom screen ... All I want on there is a "welcome" start up screen and then the climate displayed.. I need some help can I msg you for assistance.. I'm a novice when it comes to Arduino (or below novice) and Id like to know how you managed to figure out the climate control signals and how to translate that to my LCD. Thanks in advance
 
#42 ·
#30 · (Edited)
You can completely seperate the climate control data cables from the steering wheel adapter kit, but to be able to use the steering wheel buttons with your after market head unit you should keep steering wheel button cables attached to the steering wheel adapter, I just added two cables in parallel to connect arduino. With this way, I can control head unit and I can set the clock attached to my arduino lcd at the same time
 
#32 ·
W
[QUOTE = "mendilli2, publicación: 5489103, miembro: 248618"]
aquí hay un pequeño video
[MEDIA = youtube] jSx3QTpY-Cw [/ MEDIA]
[/CITAR]
Wooww !!!
Necesito un Cómo, ahora !!!! :)
I am trying to move the display radio non sat to the boxgloves and use a lcd colour screen instead of original screen nav. And connect everything with a Vim3l board(like rasperry)
 

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