Signals, Interfaces and Shields

Ignition Circuit:

Purpose:
The system shield ground protects against false signals induced by high voltage.

Operation:
High voltage such as secondary ignition or solenoids generate Radio Static or Radio Frequency (RF) interference. This interference could alter signals generated by low voltage ignition components. The system shield deflects RF waves directionally away from sensitive signal circuits.

Location:
The system shield ground is clear, CKT 452 and connects to pin C4 of the ECM.