Constant +12V (Battery) – keeps clock and memory settings.
. Powers the unit on only when the vehicle’s key is in the "On" or "Accessory" position. Chassis Ground
: Use heat-shrink tubing or high-quality butt connectors. Loose wires are the #1 cause of "popping" sounds or intermittent power loss.
Blaupunkt 12 Pin Wire Harness for NAPA65 In-dash Unit - eBay