The Quest for Control

sikwan

06 Tin Can
One of the many things that I thought needed attention was a way to get the Aux Heater working using the OEM remote. There were mornings where I had to run outside in my pajamas to turn on the heater because I forgot to program the timer the night before.

Since I had done it to my other vehicle, it was time to work on the Sprinter. I was curious to see if it was possible to use the stock keyless entry system in the Sprinter for my needs. Here's what I found.

IMGP0009.JPG
This is where the box resides; right behind the gauge cluster.

IMGP0010.JPG
The connector that I'm interested in.

skreem_pinout.jpg
This is the pinout for the keyless entry system.

The only pins that had any usable signals on the line when pressing the remote lock and unlock buttons were 4, 9, and 10. All were 12V lines. After some more probing, I found that pins 4 and 10 didn't have any noticeable difference except 4 was active high and 10 was active low. Only pin 9 was discernable, which was good news to me. :thumbup:

IMGP0008.JPG
Unlock signal off pin 9. A 114ms wide six point square wave.
 

sikwan

06 Tin Can
IMGP0006.JPG
Pressing the lock button yields a 948ms wide six point square wave.

IMGP0007.JPG
The width of one of the three point square waves is 76ms.

I haven't decided how I'm going to decipher the signal, but at least the signals are different enough for me to use.

This is my initial plan.
3rd unlock will open the Fan-tastic Vent.
4th unlock will open the driver's/passenger's window and Fan-tastic Vent.

2nd lock will turn on the heater.

All will work within a certain timeframe that I haven't figured out yet. It's all preliminary still. I still have to figure out the hardware, write the software, and get some sleep. :snore:

Seek
 

kkanuck

LUV my T1N
Seek, .......The Ultimate Control Wiring Guru.......I love it.

I am eager to learn......keep us posted with your most interesting quest!


Tibor
 

BaywoodBill

pre-Yuppiedom
sikwan wrote "There were mornings where I had to run outside in my pajamas to turn on the heater because I forgot to program the timer the night before."

C'mon, seek, it doesn't get that cold in San Jose.
 

sikwan

06 Tin Can
Thanks guys!

sikwan wrote "There were mornings where I had to run outside in my pajamas to turn on the heater because I forgot to program the timer the night before."

C'mon, seek, it doesn't get that cold in San Jose.
:shhh:...okay, maybe I'm just lazy. :smirk:
 

Black Sprinter

New member
Richard sure jumped on that bit about the pajamas, didn't he?
One of the many things that I thought needed attention was a way to get the Aux Heater working using the OEM remote. There were mornings where I had to run outside in my pajamas to turn on the heater because I forgot to program the timer the night before.

Since I had done it to my other vehicle, it was time to work on the Sprinter. I was curious to see if it was possible to use the stock keyless entry system in the Sprinter for my needs. Here's what I found.

View attachment 1343
This is where the box resides; right behind the gauge cluster.

View attachment 1344
The connector that I'm interested in.

View attachment 1342
This is the pinout for the keyless entry system.

The only pins that had any usable signals on the line when pressing the remote lock and unlock buttons were 4, 9, and 10. All were 12V lines. After some more probing, I found that pins 4 and 10 didn't have any noticeable difference except 4 was active high and 10 was active low. Only pin 9 was discernable, which was good news to me. :thumbup:

View attachment 1345
Unlock signal off pin 9. A 114ms wide six point square wave.
Nice scope!!:drool:
bill
 

sikwan

06 Tin Can
Richard sure jumped on that bit about the pajamas, didn't he?
No kidding. It must be an Australian thing. :D

I know of another Australian in the Bay Area that jumped on it when I mentioned that I wore one of those clean room garbs (bunny suits). :bounce:

Seek
 

poolmike

'05 2500 SHC
Seek...After all of this effort you will still have to run outside in you pajamas to get your remote to do anything to your van.:smirk:
 

sikwan

06 Tin Can
Seek...After all of this effort you will still have to run outside in you pajamas to get your remote to do anything to your van.:smirk:
:laughing: You're not kidding on the remote. Hopefully I can fix the range as well.

Seek

ps. And next time, I'll change into my work clothes. :tongue:
 

sikwan

06 Tin Can
So, how did it turn out?
It didn't. At least not yet. :D

I have a long ways to go before I have anything solid. I'm quite positive that it won't become vaporware too.

There are a few things that I need to iron out before I go into the design phase.

1. What type of input would I need to enable/disable the aux heater timer. What kind of buffer do I need between the microcontroller and the timer?

2. What type of control do I want for the Fan-Tastic Vent, how do I control it?

3. Same thing for the power windows as #2. Also, do I integrate it into the black box or do I drive an external relay? Do I want up and down or just down (having kids around is safety factor)?

I have to figure out the inputs, outputs, and feedback needed for the above three before I can sit down and do some laying out of the pcb, not to mention the software to do everything. I just don't think I can finish this overnight, but finish it I will. :smilewink:

Seek
 

tegimr

2003 Pass 140 289000 mile
It didn't. At least not yet. :D

I have a long ways to go before I have anything solid. I'm quite positive that it won't become vaporware too.

. . .

I have to figure out the inputs, outputs, and feedback needed for the above three before I can sit down and do some laying out of the pcb, not to mention the software to do everything. I just don't think I can finish this overnight, but finish it I will. :smilewink:

Seek
Hmmm. Would a PLC work well for preliminary work? Then pcb later?
 

sikwan

06 Tin Can
Finally got some time to look into this and decided that instead of reinventing the wheel, I'm going to reuse a current design that I have access to. It has mostly everything I need and probably more than what I really need to accomplish this task. The best thing is the cost will be minor because it's not a ground up design.

A modified version of the original schematic.
sch.jpg
Input/output signals are the gray squares and the micro-controller programming will be modified slightly.

PCB Board
pcb.JPG
Some traces need to be cut and rerouted.

Going back to these two pictures...


Unlock signal. 6 square waves within 114ms.


Lock signal. 6 square waves within 948ms.

...I will be programming the counter inside the micro-controller to read square waves within 500ms or 1/2 a second.

6 square waves within 500ms will be the unlock signal.
3 square waves within 500ms will be the lock signal.

I may have to increase or decrease the 500ms interval depending on how the lock signal behaves. Since I'm dropping the remaining 3 lock signals, it may interfere with the overall reading. I also forgot to measure the signals to see if there is any overlap, meaning if I pressed the unlock button rapidly, how close are the consecutive 114ms six point square waves from each other. :thinking:

To reiterate:
3rd unlock will open the Fan-tastic Vent.
One of the 12V mosfets will be powering the vent. I might also crack the windows to provide air flow. I will reroute the switch to one of the micro-controller inputs, this way I can have the micro-controller control the fan (open/close) either with the key in the run position or a timed control.

4th unlock will open the driver's/passenger's window and Fan-tastic Vent.
Since the windows are 25A fused and due to the arrangement of the switches, I had no choice but to include 2 Bosch relays into the mix. I'll use two of the grounding mosfets to activate the 2 relays independently.

I'm also trying to see if I can add some signal lines (input to the micro-controller) so that when I double-click the down position switch twice, the window will roll down automatically for either the driver or passenger.

2nd lock will turn on the heater.
I was going to go off the timer heater, but I'll instead supply a timed 12V to the same output of the 7 day timer module. Much easier than hacking into the timer. This timed output 12V will turn off once the key is in the run position.

That's it for now. :snore:
 

anomaly

Member
Totally out-geeked

I thought I was demonstrating geek-cred by pulling the dash apart and posting a wiring diagram for my stereo (that I horked from someone else.)

You've completely raised the bar now and there's no way I can attain your geekiness factor. I submit. You win! :clapping:

I never would have thought to go that direction to accomplish that kind of goal. Pretty cool!
 

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