Circuit Operation
WARNING: This page is about a different variant/trim than selected.
The Immobilizer-ECU is energized by the MFI relay when the ignition switch is turned "ON". The ECM transmits a signal from scan tool MB991958 to the immobilizer-ECU as it is. In the same way, a signal from the immobilizer-ECU is also transmitted to scan tool MB991958 as it is.