Inspection Procedure

WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.

READ VALUE OF HAND-HELD TESTER (TRANSPONDER KEY ECU (SWITCH CONDITION))
1. Connect the hand-held tester to the DLC3.
2. Turn the ignition switch to the ON position, and turn the hand-held tester main switch ON.
3. Select the item "IMMOBILIZER" in the DATA LIST, and read its value displayed on the hand-held tester.
  Standard:
  - SET: Ignition switch ON
  - UNSET: Without key
  OK: NORMAL
NG: Go to next step.
CHECK WHETHER ENGINE STARTS WITH OTHER KEYS
1. Check whether the engine starts with the other keys for the vehicle.
  Standard:
  - Engine starts.
OK: RE-REGISTER OR REPLACE KEY THAT WILL NOT START ENGINE

NG: Go to next step.
READ VALUE OF HAND-HELD TESTER (TRANSPONDER KEY ECU (SWITCH CONDITION))
1. Connect the hand-held tester to the DLC3.
2. Turn the ignition switch to the ON position, and turn the hand-held tester main switch ON.
3. Select the item "ANTENNA COIL" in the DATA LIST, and read its value displayed on the hand-held tester.
  Standard:
  - OK: NORMAL
  - NG: FAIL
NG: REPLACE TRANSPONDER KEY AMPLIFIER

OK: Go to next step.
CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - TRANSPONDER KEY AMPLIFIER)
1. Disconnect the T20 ECU and I13 amplifier connectors.
  
  Fig 1: Disconnecting T20 ECU & I13 Amplifier Connectors
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance of the wire harness side connectors.
  Standard
  
  Fig 2: Measuring Resistance Between Transponder Key ECU - Transponder Key Amplifier Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step.
CHECK OPERATION OF TRANSPONDER KEY AMPLIFIER
1. After replacing the transponder key amplifier, check that the engine starts.
  Standard:
  - Engine starts.
NG: REPLACE TRANSPONDER KEY ECU ASSY

OK: NORMAL (TRANSPONDER KEY AMPLIFIER DEFECTIVE)