Factory Alarm Starter Kill Bypass - Theft Computer Wire Ground

Electricalintermediate✓ OP Confirmed

Problem

The factory alarm system on the MKIII Supra activates and engages the starter kill, preventing the car from cranking. Standard reset methods (locking/unlocking doors and trunk with key) no longer work, often due to corroded or worn-out door lock cylinders.

Car will not crank or startRed alarm indicator light blinking on dashStrong battery and lights but no engine crank when key is turnedKey-in-lock reset procedure (driver door, passenger door, trunk) no longer deactivates alarmDoor lock cylinders may be corroded, gunked up, or turn freely without engagingAlarm horn and lights may go off intermittently

Root Cause

The factory alarm system's door lock sensors become corroded or worn out over time, preventing the key-in-lock reset procedure from properly disarming the alarm. Once the alarm cannot be properly disarmed, the starter kill relay remains engaged and blocks the starter circuit, preventing the engine from cranking.

Confidence

Moderate confidence — Original poster confirmed this resolved the issue

View Original Thread →Posted February 2008 on SupraForums.com