Since electricity is colour blind... you can never be 100% sure with colour codes.
The power lead has 4 pins and is supposed to be black. Pin 1 should be (Black) Ground/Negative supply on battery
Pin 2 (Blue) should not be connected, Pin 3 (Yellow) should be +ve 12V when the ignition is on and Pin 4 (red) should be +ve 12V at all times. Both 3 & 4 need a 3A fuse in them.
Connecting Pin 1 and 3 only will not work, you need 1,3 and 4 connected. 3 and 4 could at least for testing just be shorted together.