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Failure Symptoms & Circuit Tests

  1. Determine failure symptom. Proceed to indicated circuit test.
  2. If theft deterrent or door lock control functions cannot be set or activated, go to appropriate THEFT DETERRENT ECU POWER CIRCUIT TEST.
  3. If theft deterrent system does not deactivate when ignition switch is turned to ON or ACCESSORY position, go to appropriate THEFT DETERRENT IGNITION SWITCH CIRCUIT TEST.
  4. If starter does not operate even when theft deterrent system is deactivated, go to appropriate THEFT DETERRENT STARTER CUT SYSTEM CIRCUIT TEST.
  5. If theft deterrent system does not unlock doors when key is left in ignition switch (key confinement prevention), go to appropriate THEFT DETERRENT KEY UNLOCK WARNING SWITCH CIRCUIT TEST.
NOTE: For theft deterrent ECU terminal and circuit identification, see Fig 1 or Fig 2 and appropriate THEFT DETERRENT ECU TERMINAL IDENTIFICATION table.
ES250 THEFT DETERRENT ECU TERMINAL ID

ECU Connector & Terminal No. Circuit Identification
A1 Theft Deterrent Indicator Light
A2 Horn Relay
A3 Taillight Control Relay
A4 Luggage Compartment Key Unlock
A5 Theft Deterrent Horn
A6 Power (Dome Fuse)
A7 Door Courtesy Switches (Common Circuit)
A8 Engine Compartment Courtesy Switch
A9 Luggage Compartment Courtesy Switch
A10 Ignition Switch (Accessory)
A11 Rear Door Lock Switch
A12 Headlight Control Relay
B1 Starter Relay
B2 Ignition Switch (ON)
B3 Door Lock Motor
B4 Door Lock Motor
B5 (1) N/A
B6 Key Unlock Warning Switch
B7 Door Lock Switch (Front Right)
B8 Power (Circuit Breaker)
B9 Door Key Lock/Unlock Switch (Front Left/Unlock)
B10 Door Lock Switch (Front Left)
B11 Right Front Door Courtesy Switch (A7 Circuit)
B12 Left Front Door Courtesy Switch (A7 Circuit)
B13 Door Key Lock/Unlock Switch (Front/Lock)
B14 ECU Ground
B15 Door Key Lock/Unlock Switch (Front Right/Unlock)
B16 Door Manual Lock/Unlock Switch (Front/Lock)
B17 Door Manual Lock/Unlock Switch (Front/Unlock)
B18 (1) N/A
(1) Information is not available from manufacturer.
Fig 1: Theft Deterrent ECU Harness Connector Terminal ID (ES250)
G90E18873Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
LS400 THEFT DETERRENT ECU TERMINAL ID

ECU Connector & Terminal No. Circuit Identification
A1 Starter Relay
A2 Ignition Switch (ON)
A3 Door Lock Motors (Unlock)
A4 Door Lock Motors (Lock)
A5 Luggage Compartment Opener Sol.
A6 Key Unlock Warning Switch
A7 Unlock Detect Switch (Front Right)
A8 Circuit Breaker (Door)
A9 Theft Deterrent Indicator Light
A10 Door Key Switch Unlock (Front Left)
A11 Unlock Detect Switch (Front Left)
A12 Door Open Detect Switch (Front Right)
A13 Door Open Detect Switch (Front Left)
A14 Door Key Switch Lock (Front Left)
A15 Door Key Switch Unlock (Front Right)
A16 ECU Ground
A17 Door Lock Control Switch (Lock)
A18 Door Lock Control Switch (Unlock)
A19 Luggage Compartment Opener Switch
A20 ECU Power
B1 Luggage Compartment Key Switch
B2 Door Unlock Detection Switch (Rear)
B3 Door Courtesy Switch (All)
B4 Theft Deterrent Horn
B5 Headlight Control Relay
B6 (1) N/A
B7 Ignition Switch (Accessory)
B8 Power Window Main Relay
B9 (1) N/A
B10 Luggage Compartment Courtesy Switch
B11 Horn Relay
B12 Hood Courtesy Switch
B13 Taillight Control Relay
B14 (1) N/A
(1) Information is not available from manufacturer.
Fig 2: Theft Deterrent ECU Harness Connector Terminal ID (LS400)
G91I16319Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002