Hybrid Vehicle Immobilizer System Inspection

WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

INSPECTION TRANSPONDER KEY COIL CONTINUITY
Check that continuity exists between terminal 1 and 2.

Fig 1: Testing Transponder Key Coil
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If continuity is not as specified, replace the coil.
Inspect Transponder Key ECU Circuit
Disconnect the connector from the ECU and inspect the connector on the wire harness side.

Fig 2: Identifying Transponder Key ECU Terminals (Wire Harness Side)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 3: Transponder Key ECU Terminal Specifications (Wire Harness Side)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the circuit is not as specified, try replacing the ECU with a new one.

If the circuit is not as specified, inspect the circuits connected to other parts.
Inspect Transponder Key ECU
1. With the connector connected, connect the positive (+) lead from the analog type tester to terminal 8 and the negative (-) lead to the body ground.
  
  Fig 4: Testing Transponder Key ECU
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check that there is battery voltage when the ignition switch turned ON.
3. Check that the tester needle swings strongly for approx. 1 sec. when the engine is started using the ignition key.