Assembly:
Obviously there are many ways of building the control circuit. I chose to use a PCB breadboard since the soldering pads already exist and there are groups of pads with common continuity so you don’t have to use as many jumpers. One recommendation I will give is to not unnecessarily limit yourself in terms of room to attach components. I bought a small project box and cut down my board to fit, but ended up spending about twice as long putting everything together due to the confined space. Once you add in the screw terminals (each terminal denoted by a number in parentheses in the schematic) you end up with a significant loss of real estate.
Programming of the PICAXE-08M microcontroller is very simple. There are many tutorials online about how to program them, which requires a serial port, a few additional resistors, and a means to connect individual pins of the microcontroller to the serial connection. A google search should give many results for the physical configuration for programming, or you can just take a look at the manual (http://www.rev-ed.co.uk/docs/picaxe_manual1.pdf). I have attached the actual programming code I used to this post in .bas format, which can be uploaded with the PICAXE software, which I then put in a zip file. The .bas file can be opened in notepad to view the code.
At this point there’s not much else to say about building it, aside from giving due consideration to testing continuity and ensuring proper polarity/arrangement of the capacitors and 2N3904 transistor once everything’s in place. Also important is ensuring that the wires leaving the box to attach to the vehicle wiring are long enough to reach their destinations (I left 5’ per wire, which gave versatility of where I placed the box), and LABEL THE OUTGOING WIRES SO YOU DON’T MIX THEM UP.
Here are a couple pictures of my final product:
![]()
![]()
------------------------------------------------------
One last test:
Once the circuit is fully built, you can use a 9V battery to verify that it’s working. Apply 9V between the reference voltage point (3) and ‘-‘ point (2) from the schematic. If the switches are enabled properly, you should be able to measure three short pulses of continuity between points (3) and (4) after the 8 second delay, as well as between points (3) and (5). Repeat with the different switch configurations to make sure it works as expected. As well, with the switches enabled, jumper point (1) to point (3) to simulate accessory power is available to ensure that the system doesn’t operate.
------------------------------------------------------
Installation:
Installation was fairly simple. After pulling off the trim plate on the console and removing the connectors, the bottom side of the heated seat controls is exposed. The following post shows how to remove the trim:
http://www.g8board.com/forums/showpost.php?p=586357&postcount=10
This is what it looked like after removing the trim:
![]()
Depending on where the box is placed, the wiring may have to be snaked through to the console area. I found it easier to get the wires in place by removing the small plate shown in the photo below with the screw partly raised/removed.
![]()
Use the T-tap connectors to wire points (3), (4), and (5) according to the schematic and the noted wire colors.
![]()
Replace the trim plate and remove the passenger side panel by the radio as shown below.
![]()
Snake the remaining two wires through and use the t-tap connectors to tap into the rear of the 12V accessory outlet. I already had my GPS wired in, so I just used two larger (blue) T-tap connectors to splice onto those wires. Just make sure you get the polarity right on the connections by using a multimeter to measure the 12V polarity.
![]()
Once all wires are tapped in, a good spot for the unit is needed. I zip-tied mine in the left corner under the dash so I could still have access to the switches, but it would still be quite hidden and not get in the way.
![]()
After the installation, set both switches to enable control and try it out.
Here’s a quick video of mine in action:
If the video doesn't load:
EDIT: Something odd happened with the attachment. The file that can be extracted from the attached zip file is now, for whatever reason, another zip file without an extension. Please add the .zip extension to the file that is extracted, which, after further extraction, will provide the .bas file that is needed by the editor.
Obviously there are many ways of building the control circuit. I chose to use a PCB breadboard since the soldering pads already exist and there are groups of pads with common continuity so you don’t have to use as many jumpers. One recommendation I will give is to not unnecessarily limit yourself in terms of room to attach components. I bought a small project box and cut down my board to fit, but ended up spending about twice as long putting everything together due to the confined space. Once you add in the screw terminals (each terminal denoted by a number in parentheses in the schematic) you end up with a significant loss of real estate.
Programming of the PICAXE-08M microcontroller is very simple. There are many tutorials online about how to program them, which requires a serial port, a few additional resistors, and a means to connect individual pins of the microcontroller to the serial connection. A google search should give many results for the physical configuration for programming, or you can just take a look at the manual (http://www.rev-ed.co.uk/docs/picaxe_manual1.pdf). I have attached the actual programming code I used to this post in .bas format, which can be uploaded with the PICAXE software, which I then put in a zip file. The .bas file can be opened in notepad to view the code.
At this point there’s not much else to say about building it, aside from giving due consideration to testing continuity and ensuring proper polarity/arrangement of the capacitors and 2N3904 transistor once everything’s in place. Also important is ensuring that the wires leaving the box to attach to the vehicle wiring are long enough to reach their destinations (I left 5’ per wire, which gave versatility of where I placed the box), and LABEL THE OUTGOING WIRES SO YOU DON’T MIX THEM UP.
Here are a couple pictures of my final product:
------------------------------------------------------
One last test:
Once the circuit is fully built, you can use a 9V battery to verify that it’s working. Apply 9V between the reference voltage point (3) and ‘-‘ point (2) from the schematic. If the switches are enabled properly, you should be able to measure three short pulses of continuity between points (3) and (4) after the 8 second delay, as well as between points (3) and (5). Repeat with the different switch configurations to make sure it works as expected. As well, with the switches enabled, jumper point (1) to point (3) to simulate accessory power is available to ensure that the system doesn’t operate.
------------------------------------------------------
Installation:
Installation was fairly simple. After pulling off the trim plate on the console and removing the connectors, the bottom side of the heated seat controls is exposed. The following post shows how to remove the trim:
http://www.g8board.com/forums/showpost.php?p=586357&postcount=10
This is what it looked like after removing the trim:
Depending on where the box is placed, the wiring may have to be snaked through to the console area. I found it easier to get the wires in place by removing the small plate shown in the photo below with the screw partly raised/removed.
Use the T-tap connectors to wire points (3), (4), and (5) according to the schematic and the noted wire colors.
Replace the trim plate and remove the passenger side panel by the radio as shown below.
Snake the remaining two wires through and use the t-tap connectors to tap into the rear of the 12V accessory outlet. I already had my GPS wired in, so I just used two larger (blue) T-tap connectors to splice onto those wires. Just make sure you get the polarity right on the connections by using a multimeter to measure the 12V polarity.
Once all wires are tapped in, a good spot for the unit is needed. I zip-tied mine in the left corner under the dash so I could still have access to the switches, but it would still be quite hidden and not get in the way.
After the installation, set both switches to enable control and try it out.
Here’s a quick video of mine in action:
|
|
|
If the video doesn't load:
EDIT: Something odd happened with the attachment. The file that can be extracted from the attached zip file is now, for whatever reason, another zip file without an extension. Please add the .zip extension to the file that is extracted, which, after further extraction, will provide the .bas file that is needed by the editor.
9
