Inspection Procedure 3: Theft-Alarm Horn Does Not Sound While The Theft-Alarm System Is Triggered: Notes

WARNING: This page is about a different car, the 2008 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.

Fig 1: Theft-Alarm Horn Circuit Diagram

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.