Section 635 (Theft Deterrent System - Diagnostics)

WARNING: This page is about a different car, the 2004 Toyota Camry. However, it is still accessible from the selected car via links, so may be relevant.

How To Proceed With Troubleshooting
Customer Problem Analysis Check
Location
Terminals Of Ecu
Problem Symptoms Table
Ecu Power Source Circuit
Theft Deterrent Horn Circuit
Indicator Light Circuit