Using LEXUS Scan Tool
- Insert registered master key in ignition. Turn ignition on.
- Perform this step within 2 minutes. Select LS430, IMMOBILIZER, KEY CODE UTILITY and TRANSPONDER CODE REGISTRATION from LEXUS scan tool.
- Perform this step within 20 seconds. Remove master key.
- Perform this step within 10 seconds. Insert master key to be registered in ignition. Security indicator should flash. After one minute, additional master key is registered. Security indicator should turn off.
Registration Of Key Number (Using LEXUS Scan Tool)
- Insert registered master key in ignition. Turn ignition on.
- Select LS430, IMMOBILIZER, KEY CODE UTILITY and KEY NO. REGISTRATION.
- Insert key number of key number plate according to Lexus scan tool screen. Observe scan tool and ensure key number is registered to transponder key ECU.
Change Of Key Number (Using LEXUS Scan Tool)
- Insert registered master key in ignition. Turn ignition on.
- Select LS430, IMMOBILIZER, KEY CODE UTILITY and KEY NO. CHANGE.
- Insert key number of key number plate according to Lexus scan tool screen. Observe scan tool and ensure key number is changed. Remove master key.
- Insert master key in ignition. Turn ignition on.
- Perform this step within 2 minutes. Select LS430 from menu. Select IMMOBILIZER, KEY CODE UTILITY and TRANSPONDER CODE REGISTRATION. After these operations, proceed to additional operations following prompts on tester screen.
- Perform this step within 10 seconds. Remove master key.
- Procedure is now completed. Key code should now be erased. If key cannot be removed from ignition, key code deletion is canceled. Security indicator will turn off. Repeat procedure from step 1 .
TROUBLE SHOOTING
Note. Perform immobilizer system self-diagnostics before performing trouble shooting. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM.
| Problem | Inspect |
|---|
| Immobilizer Not Set (Engine Starts W/Incorrect Key Codes) | (1) Power Source Circuit; (2) Transponder Key ECU |
| Engine Does Not Start | (3) Key; (2) Wiring Harness; (4) Transponder Key Amplifier Circuit; (2) Transponder Key ECU |
| Security Indicator Is Always On | (5) Security Indicator; (2) Wiring Harness; (6) Theft Deterrent ECU; (2) Transponder Key ECU |
| Security Indicator Is Always Off | (2) Wiring Harness; (6) Theft Deterrent ECU; (2) Transponder Key ECU |
| (1) See POWER SOURCE CIRCUIT under SYSTEM TESTS. (2) Check for open or short circuits in wiring. See WIRING DIAGRAMS . Perform PIN VOLTAGE TESTS . Repair or replace components as necessary. (3) Ensure key used to start engine is registered. Also check if vehicle will start with other registered keys. (4) Check transponder key amplifier circuit. If wiring is okay, see WIRING DIAGRAMS . (5) Complete automatic registration mode. See NEW TRANSPONDER KEY CODE under PROGRAMMING. (6) See ANTI-THEFT SYSTEMS - LS430 article. |
| (1) | See POWER SOURCE CIRCUIT under SYSTEM TESTS. |
| (2) | Check for open or short circuits in wiring. See WIRING DIAGRAMS . Perform PIN VOLTAGE TESTS . Repair or replace components as necessary. |
| (3) | Ensure key used to start engine is registered. Also check if vehicle will start with other registered keys. |
| (4) | Check transponder key amplifier circuit. If wiring is okay, see WIRING DIAGRAMS . |
| (5) | Complete automatic registration mode. See NEW TRANSPONDER KEY CODE under PROGRAMMING. |
| (6) | See ANTI-THEFT SYSTEMS - LS430 article. |
TROUBLE SHOOTING SYMPTOMS
RETRIEVING DIAGNOSTIC TROUBLE CODES
- Connect LEXUS scan tool to Data Link Connector 3 (DLC3) located under left side of instrument panel. Turn ignition switch to ON position. Using scan tool, check DTCs and freeze frame data. If DTC 99 is retrieved, see «TROUBLE SHOOTING SYMPTOMS»(ref-26717-S09401078922001010800000) table under TROUBLE SHOOTING.
- If any other DTCs are retrieved, see «ENGINE IMMOBILIZER DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-26717-S15676096502001010800000) table. Each DTC will be displayed in order, starting with lowest DTC.
| DTC | Definition |
|---|
| B2780 | Key Unlock Warning Switch Malfunction |
| B2793 | Transponder Chip Malfunction |
| B2794 | Unmatched Encryption Code |
| B2795 | Unmatched Key Code |
| B2796 | No Communication In Immobilizer System |
| B2797 | Communication Malfunction No. 1 |
| B2798 | Communication Malfunction No. 2 |
| B2799 | Engine Immobilizer System |
ENGINE IMMOBILIZER DTC DEFINITIONS
ERASING DIAGNOSTIC TROUBLE CODES
If a DTC is a present code, it will clear as DTC is retrieved. If DTC is a past code, clear DTC using LEXUS scan tool.
DTC 2799: ENGINE IMMOBILIZER SYSTEM
Check Gray/Red and Gray/Green wires between transponder key ECU and ECM. Repair wiring as necessary. If wiring is okay, replace ECM.
