Dummy pinSKU: M120-55780
Seals the unused openings in the connector.
This way you keep the ECU connector watertight and no dust or dirt can get into the connector.
The dummy pins are already installed at the Prefab Cable trees.
With a DIY cable harness you will have to order these dummy pins. You then need several.
The connector is NOT watertight if not all positions are occupied by wiring or dummy pins and corrosion will occur on the connector if moisture enters the connector.
I once had a custumer that did not install the dummy pins. His ECU connector rusted away in very little time as his ECU was in a wet place and tortured with a waterhose. He was a real dummy...