Shield Assembly

Shield Assembly

If you've opted to assemble your shield yourself, great.  After you assemble it, you'll need to test your work for shorts and other potential problems.  If you have problems with a self assembled shield we'll do everything we can to help resolve the issue, but if any repairs are needed, you will be charged accordingly.

That being said, let's get to it, it's not very difficult.

The shield is make up of different abilities and depending on which ones were selected dictates which parts will need to be assembled.  There may some areas where no parts will be installed, this is normal.

To summarize, this is the order I recommend.

First install everything regarding the power supply and testing it with a multi meter.

After that is done, you install your EEPROM and ATTiny.

Next comes your accessories, they are made up of:

  • Audio switching
  • CAN bus
  • GPS
  • HD Radio
  • Input/output connections
  • Temperature sensors

Layout Summary


Each area is marked in a distinct color.

Red - Power supply and related components

Orange - EEPROM and ATTiny

Magenta - Audio components

Green - CAN Bus

Blue - HD Radio

Pink - GPS.  Note GPS and HD Tuner share components

Purple - Input and output

Yellow - Temperature Sensors


Note for all areas.  Some of the resistor values won't match what's printed on the PCB.  Values supplied are 1k, 4.7k and 10k.  The 1k and 4.7k are correct.   The 10k and 100k are incorrect.  Replace 10k with 1k, and 100k with 10k.

Power Supply

The power supply consists of:

  • Connection header
  • Rectifier diodes
  • Filter capacitors
  • Inductor
  • Voltage suppressor
  • Regulator
  • Optoisolator
  • LED driver
  • Mosfet
  • Transistor
  • Resistors

I recommend starting with the smallest components first, so let's to the resistors.  The top section is 10k, 4.7k, 4.7k then 10k.  You might as well do the capacitor that's there too.  All of the little blue caps are the same value, so grab one and go.

In the middle red area, from left to right, we have a capacitor, MOSFET, resistors, transistor, capacitor, voltage regulator, optoisolator.

Again start with the resistors.  The three leftmost are 1k with a 10k to the right.  Then do the capacitors.  The right one is polarized and can only be installed one way.  If you install it backwards it may explode.  The ground pin is the top on the PCB.  You can identify the ground pin in the capacitor by one of a couple of ways.  The pin is usually shorter, but more failsafe is the marking on the capacitor.  The side with the grey bar is ground.

Next install the MOSFET, the metal backed side faces left towards the white line.  

Then do the transistor and voltage regulator carefully noting the orientation printed on the PCB.  The transistor is on the left of the capacitor, and the regulator on the right.  Finally Install the optoisolator.  Pin 1 is marked with the little circle in the top left, it faces the voltage regulator.  Again note markings on PCB.

The bottom section is the power filtering.  Almost everything here is polarized, meaning you need to pay attention to which way the pieced are orientated, or it won't work.

Starting top left, working right you have an LED driver with a dioded directly under it.  Two main filter caps to the right with two more diodes right of them.  The rightmost piece is the wire connectors.  Under the filter caps are the voltage suppressor and inductor at the very bottom.

For this section I start with the three diodes.  They are clearly marked with a grey band, these NEED to match what's printed on the PCB.  After that do the LED driver.  This gets installed in the spot marked as a 1k resistor.  This was a last minute part change.  The flat side of the driver faces the top of the PCB.  After that is done do the inductor and voltage suppressor.  *NOTE* Some voltage suppressors are marked like the diodes with a grey band, some are not.  If yours is marked make sure it matches the printing.  If it's not marked you can install it in any direction.  The inductor can be installed any way.  When those are done your last pieces are the two capacitors.  The left one has the ground pin on the top, the right one has ground on the bottom.


Once you have installed everything you NEED to test to make sure it's working otherwise you may fry everything on the shield and Arduino.

On the power connector you have three pins, ground, 12v and ACC.  Get a power supply that ranges between 7 and 15 volts.  12 is ideal but not mandatory.

Hookup power to the ground and middle 12v pin.  Get your multimeter and set it to read DC voltage.  First start with the screw terminals and make sure you've hooked up the wires the correct way.  Keeping your ground probe on the ground screw touch both sids of the diodes.  With ACC disconnected the top one should show power on the left side, but not the right.  The bottom one should have power on both sides.  You may notice a 0.6 volt drop across the diodes.  This is normal.

Probe the inductor, you should have power on both sides.  The voltage suppressor should have power on the right side.

Once that is all verified we need to check the voltage regulator.   The easiest place to check is the top IC spot, where the ATTiny gets soldered.  The bottom right pin (pin 4) is ground, and the top left (pin 8) is VCC, it should read 3.3 volts, or very close to it.  I suggest also probing the optoisolator.  Probe across the top two pins, you should read the same 3.3 volts.

Once that has been verified, hookup power to the accessor line.  You can just switch from 12v to ACC.  The optoisolator should now read 0 volts.  One last probe, ground to the screw terminal, and positive to the VIN line that goes to the Arduino.  You can see this in the picture right above where the orange and red box touch near the middle.

The last two things are the orange boxes.  Install the EEPROM, part number 25LC040 noting pin 1 faces right.  And finally the ATTiny up top, pin 1 facing left.


If you like you can do one last test.  Hookup power again to your 12v line, but not the ACC line.  Touch your multimeter to the VIN line, you should have 0 volts.  Touch power to the ACC line momentarily.  After power is disconnected you should have power on VIN for 1 minute before it turns off.