Trouble Shooting: Notes

WARNING: This page is about a different car, the 2002 Lexus GS 430 and 2002 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.

Trouble shooting of an anti-theft system complaint begins with verification of the customer problem. If problem occurs, go to step 3. If problem does not occur, go to next step.
If problem does not occur, review conditions under which problem occurred for customer and try to duplicate those conditions. For example, if the problem occurs on rainy days or during high humidity conditions, sprinkle water onto vehicle and see if malfunction occurs. DO NOT sprinkle water directly into engine compartment or onto electronic components. Visually inspect for signs of mechanical and electrical damage. Inspect for blown fuses and damaged relays. Inspect for loose or corroded connections, damaged wiring harnesses and/or switches. Check for a broken or partially broken wire inside insulation, which could cause system malfunction but prove good in a continuity/voltage check with system disconnected. Ensure any aftermarket electronic equipment is properly installed. If fault is found, repair as necessary.
Inspect the diagnostic system of the multiplex communication system. See PRE-CHECK under SELF-DIAGNOSTIC in MULTIPLEX COMMUNICATION SYSTEM article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT.

Determine problem symptom. See PROBLEM SYMPTOM INDEX .

PROBLEM SYMPTOM INDEX

Symptom

Suspected Area ⁽¹⁾

System Cannot Be Set

⁽²⁾⁽³⁾⁽⁴⁾⁽⁵⁾⁽⁶⁾⁽⁷⁾⁽⁸⁾⁽⁹⁾

System Cannot Be Canceled When Ignition Switch Is Turned To ON With Key

⁽³⁾⁽¹⁰⁾⁽¹¹⁾⁽⁷⁾⁽⁹⁾

System Cannot Be Canceled When Luggage Compartment Door Is Unlocked With Key

⁽⁶⁾⁽⁷⁾⁽⁹⁾

System Does Not Operate When Engine Hood Is Opened

⁽⁵⁾⁽⁷⁾⁽⁹⁾

System Does Not Operate When Ignition Switch Is Turned To ACC Without Using A Key Or Transmitter

⁽¹⁰⁾⁽³⁾⁽¹²⁾⁽⁷⁾⁽⁹⁾

Some Of The System Does Not Operate (Headlight Does Not Light Up)

⁽¹³⁾⁽⁷⁾⁽¹⁴⁾⁽⁹⁾

Some Of The System Does Not Operate (Taillight Does Not Light Up)

⁽¹⁵⁾⁽⁷⁾⁽¹⁴⁾⁽⁹⁾

Some Of The System Does Not Operate (Anti-Theft Horn Or Horn Does Not Sound)

⁽¹⁶⁾⁽¹⁷⁾⁽¹⁸⁾⁽¹⁹⁾⁽⁷⁾⁽⁹⁾

While Warning Is Given, The System Cannot Be Canceled By Unlocking The Door With Key Or Transmitter

⁽²⁰⁾⁽⁷⁾⁽⁹⁾

While Warning Is Given, The System Cannot Be Canceled By Turning The Ignition Switch To ACC Or ON With Key

⁽¹⁰⁾⁽³⁾⁽¹¹⁾⁽²¹⁾⁽⁷⁾⁽¹⁴⁾⁽⁹⁾

System Operates For More Than 60 Seconds

⁽⁹⁾

⁽¹⁾	Perform test procedures in order listed under suspected area.

⁽²⁾	Check the indicator light. See ANTI-THEFT INDICATOR LIGHT under COMPONENT TESTS.

⁽³⁾	Check the key unlock warning switch. See STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.

⁽⁴⁾	Check the door unlock detection switch. See POWER DOOR LOCKS, TRUNK LID & FUEL DOOR RELEASE article under DOOR LOCKS & ANTI-THEFT SYSTEMS in ACCESSORIES & EQUIPMENT.

⁽⁵⁾	Check the engine hood courtesy switch. See ENGINE HOOD COURTESY SWITCH under COMPONENT TESTS.

⁽⁶⁾	Check the luggage compartment door courtesy switch. See AUTOMATIC HEADLIGHTS & LIGHTING article under HEADLIGHTS in ACCESSORIES & EQUIPMENT.

⁽⁷⁾	Check the wire harness. See WIRING DIAGRAMS .

⁽⁸⁾	Check each door ECU. See PIN VOLTAGE TESTS in POWER DOOR LOCKS, TRUNK LID & FUEL DOOR RELEASE article under DOOR LOCKS & ANTI-THEFT SYSTEMS in ACCESSORIES & EQUIPMENT.

⁽⁹⁾	Check the body ECU No. 1. See BODY CONTROL SYSTEMS article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT.

⁽¹⁰⁾	Check the ignition switch. See STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.

⁽¹¹⁾	Check the RAD NO. 2 fuse.

⁽¹²⁾	Check the remote keyless entry transmitter. See REMOTE KEYLESS ENTRY SYSTEM article under DOOR LOCKS & ANTI-THEFT SYSTEMS in ACCESSORIES & EQUIPMENT.

⁽¹³⁾	Check the headlight system. See AUTOMATIC HEADLIGHTS & LIGHTING article under HEADLIGHTS in ACCESSORIES & EQUIPMENT.

⁽¹⁴⁾	Check the body ECU No. 2. See BODY CONTROL SYSTEMS article.

⁽¹⁵⁾	Check the taillight system. See AUTOMATIC HEADLIGHTS & LIGHTING article under HEADLIGHTS in ACCESSORIES & EQUIPMENT.

⁽¹⁶⁾	Check the HORN fuse.

⁽¹⁷⁾	Check the anti-theft horn. See ANTI-THEFT HORN under COMPONENT TESTS.

⁽¹⁸⁾	Check the horn. Perform the same component test as the anti-theft horn. See ANTI-THEFT HORN under COMPONENT TESTS.

⁽¹⁹⁾	Check the horn relay. See STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.

⁽²⁰⁾	Check the door key lock and unlock switch. See POWER DOOR LOCKS, TRUNK LID & FUEL DOOR RELEASE article under DOOR LOCKS & ANTI-THEFT SYSTEMS in ACCESSORIES & EQUIPMENT.

⁽²¹⁾	Check the ECU-IG fuse.

After repairs have been completed, confirm that problem has been eliminated. Operate the system under same conditions recorded for original complaint. If problem is no longer present, repair has corrected problem. If problem is still present, further diagnosis and repair is required.