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Trouble Shooting

NOTE: Prior to trouble shooting, ensure no problems exist in multiplex communications. If problems exist, repair multiplex control system before trouble shooting. See MULTIPLEX CONTROL SYSTEMS - GS300 & GS400 article.
NOTE: Check circuits and components in listed order. If circuits or components are okay, return to trouble shooting and identify next circuit to be checked.
SYMPTOM DIAGNOSIS (DOOR LOCK CONTROL SYSTEM)

Problem Inspect
Lock Or Unlock Cannot Be Operated With Door Lock Control Switch (1) Power Window Master Switch Circuit
(1) Passenger Door Lock Control Switch Circuit
(2) Driver Door ECU
(2) Passenger Door ECU
(3) Body Control ECU No. 1
Door Key Link Function Does Not Operate (1) Driver Door Key Lock & Unlock Switch Circuit
(1) Passenger Door Key Lock & Unlock Switch Circuit
(2) Driver Door ECU
(2) Passenger Door ECU
(3) Body Control ECU No. 1
Key Confinement Prevention Function Does Not Operate (1) Key Unlock Warning Switch Circuit
(3) Body Control ECU No. 2
(3) Body Control ECU No. 1
System Does Not Lock & Unlock Each Door Individually (1) Driver Door Lock Motor Circuit
(1) Passenger Door Lock Motor Circuit
(1) Left Rear Door Lock Motor Circuit
(1) Right Rear Door Lock Motor Circuit
(2) Driver Door ECU
(2) Passenger Door ECU
(2) Left Rear Door ECU
(2) Right Rear Door ECU
Luggage Compartment Opening Function Does Not Operate (1) Luggage Compartment Door Opener Switch Circuit
(1) Luggage Compartment Door Opener Motor Circuit
(3) Body Control ECU No. 1
(1) Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.
(2) See appropriate wiring diagram in POWER DOOR LOCKS, TRUNK LID & FUEL DOOR RELEASE article.
(3) Perform appropriate pin voltage test under BODY CONTROL ECU PIN VOLTAGE TESTS  under COMPONENT TESTS.
SYMPTOM DIAGNOSIS (WIRELESS DOOR LOCK CONTROL SYSTEM)

Problem Inspect
Wireless Door Lock Control System Does Not Operate (1) Wireless Door Lock Transmitter
(2) Wireless Door Lock Tuner Circuit
(2) Key Unlock Warning Switch Circuit
(3) Body Control ECU No. 2
(3) Body Control ECU No. 1
Lock Or Unlock Function Does Not Operate (2) Driver Door Key Lock & Unlock Switch Circuit
(2) Passenger Door Key Lock & Unlock Switch Circuit
(2) Driver Door Unlock Detection Switch Circuit
(2) Passenger Door Unlock Detection Switch Circuit
(2) Left Rear Door Unlock Detection Switch Circuit
(2) Right Rear Door Unlock Detection Switch Circuit
(4) Driver Door ECU
(4) Passenger Door ECU
(4) Left Rear Door ECU
(4) Right Rear Door ECU
(3) Body Control ECU No. 1
Auto Lock Function Operates When Any Door Is Opened Within 30 Seconds After Unlocking All Doors With Wireless Door Lock Control System (2) Driver Door Courtesy Light & Courtesy Switch Circuit
(2) Passenger Door Courtesy Light & Courtesy Switch Circuit
(2) Left Rear Door Courtesy Light & Courtesy Switch Circuit
(2) Right Rear Door Courtesy Light & Courtesy Switch Circuit
(4) Driver Door ECU
(4) Passenger Door ECU
(4) Left Rear Door ECU
(4) Right Rear Door ECU
(3) Body Control ECU No. 1
Wireless Door Lock Operates, But Buzzer Does Not Sound (2) Wireless Door Lock Buzzer Circuit
(3) Body Control ECU No. 1
Buzzer Sounds, But Wireless Door Lock Function Does Not Operate (3) Body Control ECU No. 1
Luggage Compartment Door Opener Does Not Operate Properly (2) Luggage Compartment Door Opener Motor Circuit
(3) Body Control ECU No. 1
(1) Check transmitter operation.
(2) Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.
(3) Perform appropriate pin voltage test under BODY CONTROL ECU PIN VOLTAGE TESTS  under COMPONENT TESTS.
(4) See appropriate wiring diagram in POWER DOOR LOCKS, TRUNK LID & FUEL DOOR RELEASE article.
SYMPTOM DIAGNOSIS (ANTI-THEFT SYSTEM)

Problem Inspect
System Cannot Be Set (1) Anti-Theft Indicator Circuit
(1) Key Unlock Warning Switch Circuit
(1) Driver Door Courtesy Light & Courtesy Switch Circuit
(1) Passenger Door Courtesy Light & Courtesy Switch Circuit
(1) Left Rear Door Courtesy Light & Courtesy Switch Circuit
(1) Right Rear Door Courtesy Light & Courtesy Switch Circuit
(1) Driver Door Unlock Detection Switch Circuit
(1) Passenger Door Unlock Detection Switch Circuit
(1) Left Rear Door Unlock Detection Switch Circuit
(1) Right Rear Door Unlock Detection Switch Circuit
(1) Engine Hood Courtesy Switch Circuit
(1) Luggage Compartment Door Courtesy Switch Circuit
(2) Driver Door ECU
(2) Passenger Door ECU
(2) Left Rear Door ECU
(2) Right Rear Door ECU
(3) Body Control ECU No. 2
(3) Body Control ECU No. 1
System Cannot Be Canceled When Ignition Is In ON Position (1) Key Unlock Warning Switch Circuit
(4) Ignition Switch Circuit
(3) Body Control ECU No. 2
(3) Body Control ECU No. 1
System Does Not Cancel When Luggage Compartment Door Is Opened With Key (1) Luggage Compartment Door Key Lock & Unlock Switch Circuit
(3) Body Control ECU No. 1
Headlights Do Not Operate Properly With System (1) Headlight Relay Circuit
(3) Body Control ECU No. 2
(3) Body Control ECU No. 1
Taillights Do Not Operate Properly With System (1) Taillight Relay Circuit
(3) Body Control ECU No. 2
(3) Body Control ECU No. 1
Hazards Do Not Operate Properly With System (1) Hazard Switch Circuit
(3) Body Control ECU No. 1
Anti-Theft Horn & Standard Horn Does Not Sound (1) Anti-Theft Horn Circuit
(1) Standard Horn Circuit
(3) Body Control ECU No. 1
During Warning Condition, System Cannot Be Canceled By Unlocking Door With Key (1) Driver Door Key Lock & Unlock Switch Circuit
(1) Passenger Door Key Lock & Unlock Switch Circuit
(2) Driver Door ECU
(2) Passenger Door ECU
(3) Body Control ECU No. 1
During Warning Condition, System Cannot Be Canceled By Unlocking Door With Transmitter (5) Wireless Door Lock Transmitter
(1) Wireless Door Lock Tuner Circuit
(3) Body Control ECU No. 1
During Warning Condition, System Cannot Be Canceled By Turning Ignition To ACC Or ON Using Key (4) Ignition Switch Circuit
(1) Key Unlock Warning Switch Circuit
(3) Body Control ECU No. 2
(3) Body Control ECU No. 1
Horns Sounded For More Than 60 Seconds (3) Body Control ECU No. 1
(1) Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.
(2) See appropriate wiring diagram in POWER DOOR LOCKS, TRUNK LID & FUEL DOOR RELEASE article.
(3) Perform appropriate pin voltage test under BODY CONTROL ECU PIN VOLTAGE TESTS  under COMPONENT TESTS.
(4) Check ignition switch. See STEERING COLUMN SWITCHES article.
(5) Check transmitter operation.
SYMPTOM DIAGNOSIS (SHIFT LOCK CONTROL SYSTEM)

Problem Inspect
Shift Lock Function Does Not Operate Properly (1) Stoplight Switch Circuit
(1) Shift Lock Solenoid Circuit
(2) Body Control ECU No. 2
(1) Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.
(2) Perform appropriate pin voltage test under BODY CONTROL ECU PIN VOLTAGE TESTS  under COMPONENT TESTS.
SYMPTOM DIAGNOSIS (LIGHT CONTROL SYSTEM)

Problem Inspect
Automatic Light Control Does Not Operate (1) Light Sensor Circuit
(1) Headlight Control Switch Circuit
(2) Body Control ECU No. 2
Automatic Turn Off Does Not Operate (1) Driver Door Courtesy Switch Circuit
(3) Ignition Switch Circuit
(4) Driver Door ECU
(2) Body Control ECU No. 2
(1) Perform circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.
(2) Perform appropriate pin voltage test under BODY CONTROL ECU PIN VOLTAGE TESTS  under COMPONENT TESTS.
(3) Check ignition switch. See STEERING COLUMN SWITCHES article.
(4) See appropriate wiring diagram in POWER DOOR LOCKS, TRUNK LID & FUEL DOOR RELEASE article.
SYMPTOM DIAGNOSIS (ILLUMINATED ENTRY CONTROL SYSTEM)

Problem Inspect
Illuminated Entry Does Not Operate Properly (1) Illumination Circuit
(2) Body Control ECU No. 2
(1) Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.
(2) Perform appropriate pin voltage test under BODY CONTROL ECU PIN VOLTAGE TESTS  under COMPONENT TESTS.
SYMPTOM DIAGNOSIS (MISCELLANEOUS)

Problem Inspect
Driver Seat Belt Warning Indicator Does Not Turn Off (1) Driver Seat Belt Buckle Switch Circuit
(2) Body Control ECU No. 2
Passenger Seat Belt Warning Indicator Does Not Turn Off (1) Passenger Seat Belt Buckle Switch Circuit
(2) Body Control ECU No. 1
Clock Light Will Not Dim (1) Clock Circuit
(2) Body Control ECU No. 2
Rear Window Defogger Does Not Operate (1) Defogger Relay Circuit
(3) Defogger Switch
(2) Body Control ECU No. 1
Body Control ECU No. 1 Does Not Operate (1) ECU Power Source Circuit No. 1
(2) Body Control ECU No. 1
Body Control ECU No. 2 Does Not Operate (1) ECU Power Source Circuit No. 2
(2) Body Control ECU No. 2
(1) Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.
(2) Perform appropriate pin voltage test under BODY CONTROL ECU PIN VOLTAGE TESTS  under COMPONENT TESTS.
(3) Check defogger switch. See appropriate wiring diagram in REAR WINDOW & SIDE MIRROR DEFOGGERS article.