Question:
corroded high voltage plates

Oxidized high voltage plates
In rare cases customers report that the metal separates from the high voltage plates and appears to be oxidized. The high voltage plates are coated with a nickel-plated copper layer which does not oxidise on its own.
The installation instruction state that the high voltage plates are to be mounted in a dry place in the engine compartment.
If for a longer time period some tiny water stream is flowing over the high voltage plates (connecting them with ground), a galvanic current flows. In this way the metal plating is transported away from the high voltage plates. Additionally, the high voltage is short-circuited and no longer effective against marten. Please place the plates in a dry location (eg mounted on distance to the car chassis). Or you can buy the higher quality equipment M176, which uses stainless steel high voltage plates mounted on special spacers.

Question:
Connector 15 ?

Customers reported that connector "15" can also be connected to the positive pole of the air flow sensor.