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System Trouble Shooting

NOTE: Instrument panel ECU is connected to tilt and telescopic ECU by use of the multiplex control system. Before performing any trouble shooting of body control system, ensure multiplex control system is operating properly. See MULTIPLEX CONTROL SYSTEMS article.

Trouble shooting is available for the following systems: anti-theft, automatic light control, illuminated entry, keyless entry, power door locks and rear wiper/washer. Determine under what conditions that system does not operate or malfunctions and then perform specified test listed under SYSTEM TESTS . See appropriate TROUBLE SHOOTING SYMPTOMS table.

TROUBLE SHOOTING SYMPTOMS (ANTI-THEFT SYSTEM)

Problem (1) Circuit To Be Inspected Perform Test No.
Anti-Theft System Cannot Be Set SECURITY Indicator Light Circuit (2)
Anti-Theft System Cannot Be Set Key Unlock Warning Switch Circuit 9
Anti-Theft System Cannot Be Set Door Courtesy Switch Circuit 12
Anti-Theft System Cannot Be Set Door Unlock Detection Switch Circuit 14
Anti-Theft System Cannot Be Set Engine Hood Courtesy Switch Circuit (2)
Anti-Theft System Cannot Be Set Instrument Panel ECU (3)
(1) If more than one circuit is to be inspected, perform test on each circuit in the order listed.
(2) See ANTI-THEFT SYSTEMS article for test procedure.
(3) Perform TEST NO. 1  and TEST NO. 2 under SYSTEM TESTS. If problem still exists, test wiring harness and instrument panel ECU. See PIN VOLTAGE TESTS .
TROUBLE SHOOTING SYMPTOMS (AUTOMATIC LIGHT CONTROL SYSTEM)

Problem (1) Circuit To Be Inspected Perform Test No.
Automatic Turn-Off Function Does Not Operate Driver's Door Courtesy Switch Circuit 12
Automatic Turn-Off Function Does Not Operate Ignition Switch Power Source 2
Automatic Turn-Off Function Does Not Operate Instrument Panel ECU (2)
(1) If more than one circuit is to be inspected, perform test on each circuit in the order listed.
(2) Perform TEST NO. 1  under SYSTEM TESTS. If problem still exists, test wiring harness and instrument panel ECU. See PIN VOLTAGE TESTS .
TROUBLE SHOOTING SYMPTOMS (ILLUMINATED ENTRY SYSTEM)

Problem (1) Circuit To Be Inspected Perform Test No.
Illuminated Entry System Inoperative Illumination Circuit 3
Illuminated Entry System Inoperative Instrument Panel ECU (2)
(1) If more than one circuit is to be inspected, perform test on each circuit in the order listed.
(2) Perform TEST NO. 1  and TEST NO. 2 under SYSTEM TESTS. If problem still exists, test wiring harness and instrument panel ECU. See PIN VOLTAGE TESTS .
TROUBLE SHOOTING SYMPTOMS (KEYLESS ENTRY SYSTEM)

Problem (1) Circuit To Be Inspected Perform Test No.
Keyless Entry System Fully Inoperative Transmitter Operation (2)
Keyless Entry System Fully Inoperative Key Unlock Warning Switch Circuit 9
Keyless Entry System Fully Inoperative Wireless Door Lock ECU (3)
Keyless Entry System Fully Inoperative Instrument Panel ECU (4)
Lock Or Unlock Function Inoperative Door Key Lock & Unlock Switch Circuit 15
Lock Or Unlock Function Inoperative Door Unlock Detection Switch Circuit 14
Lock Or Unlock Function Inoperative Instrument Panel ECU (4)
Automatic Lock Function Operates Even If Any Door Is Opened Within 30 Seconds After All Doors Are Unlocked With Keyless Remote Door Courtesy Switch Circuit 12
Automatic Lock Function Operates Even If Any Door Is Opened Within 30 Seconds After All Doors Are Unlocked With Keyless Remote Instrument Panel ECU (4)
(1) If more than one circuit is to be inspected, perform test on each circuit in the order listed.
(2) Perform BASIC FUNCTION TEST under SYSTEM TESTS in KEYLESS ENTRY SYSTEMS article.
(3) See KEYLESS ENTRY SYSTEMS article for testing of wireless door lock ECU.
(4) Perform TEST NO. 1  and TEST NO. 2 under SYSTEM TESTS. If problem still exists, test wiring harness and instrument panel ECU. See PIN VOLTAGE TESTS .
TROUBLE SHOOTING SYMPTOMS (POWER DOOR LOCK SYSTEM)

Problem (1) Circuit To Be Inspected Perform Test No.
Lock Or Unlock Cannot Be Operated With Door Lock Control Switch Door Lock Control Switch 11
Lock Or Unlock Cannot Be Operated With Door Lock Control Switch Instrument Panel ECU (2)
Doors Do Not Unlock Properly When Using Key Door Key Lock & Unlock Switch 15
Doors Do Not Unlock Properly When Using Key Instrument Panel ECU (2)
Doors Lock With Key In Ignition Key Unlock Warning Switch 9
Doors Lock With Key In Ignition Instrument Panel ECU (2)
(1) If more than one circuit is to be inspected, perform test on each circuit in the order listed.
(2) Perform TEST NO. 1  and TEST NO. 2 under SYSTEM TESTS. If problem still exists, test wiring harness and instrument panel ECU. See PIN VOLTAGE TESTS .
TROUBLE SHOOTING SYMPTOMS (REAR WIPER/WASHER SYSTEM)

Problem (1) Circuit To Be Inspected Perform Test No.
Rear Wiper Inoperative Rear Wiper Switch Circuit 4
Rear Wiper Inoperative Rear Wiper Motor Circuit 5
Rear Wiper Inoperative Instrument Panel ECU (2)
Rear Washer Inoperative Rear Washer Switch Circuit 4
Rear Washer Inoperative Rear Washer Motor (3)
Rear Wiper Does Not Operate Only On High Speed Instrument Panel ECU (2)
Rear Wiper Does Not Operate When Washer Switch Is ON Rear Wiper Switch Circuit 4
Rear Wiper Does Not Instrument Panel ECU (2)
(1) If more than one circuit is to be inspected, perform test on each circuit in the order listed.
(2) Perform TEST NO. 1  and TEST NO. 2 under SYSTEM TESTS. If problem still exists, test wiring harness and instrument panel ECU. See PIN VOLTAGE TESTS .
(3) See WIPER/WASHER SYSTEMS article for testing of rear washer motor. If rear washer motor is okay, check for defective wiring harness.
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