Contents Wiring diagrams Section: Door Locks & Anti-Theft Systems All sections

Engine Immobilizer Systems: Other Lexus RX I

Door Locks & Anti-Theft Systems 2 illustrations ~1008 words

NEW TRANSPONDER KEY CODE

Note. This must be done when a new ECM is installed. The new ECM is in automatic key code registration mode. Up to 3 key codes can be registered at one time. In automatic registration mode, last key registered becomes sub-key.

Note. Master key is a Black key that opens all locks. Sub-key is a Gray key that will not open trunk, trunk main switch and glove box.

  1. Security indicator will flash until first key is inserted into ignition switch. Insert NEW key in ignition switch. Security indicator should illuminate.
  2. Once key registration is under way, security indicator should turn off. After key registration is complete, security indicator should illuminate. Remove NEW key.
  3. If programming additional keys, repeat process starting with step 1 . If additional keys do not need programming, procedure is complete. Security indicator should go out once last key (sub-key) is registered. Depress and release brake pedal at least 5 times within 15 seconds, or request automatic registration mode completion using LEXUS scan tool.
  4. After registration is complete and system is operating normally, when ignition key is removed from ignition lock cylinder, security indicator should flash indicating system is properly functioning. If a key is not inserted into ignition switch with ECM in automatic registration mode, security indicator will remain illuminated indicating keys have not been registered. If ignition key registration cannot be completed with Engine Control Module (ECM) in automatic registration mode, a code 2-1 will be displayed by security indicator, and when inserting the already registered ignition key, a code 2-2 will be displayed by security indicator.

ADDITIONAL MASTER KEY

Note. Additional master key may be registered by 2 different methods: using brake pedal and accelerator pedal, or using LEXUS scan tool. It is possible to register up to 7 master key codes including the already registered key code.

Using Brake & Accelerator Pedal

  1. Insert registered master key in ignition.
  2. Perform this step within 15 seconds. Depress and release accelerator pedal 5 times.
  3. Perform this step within 20 seconds. Depress and release brake pedal 6 times. Remove master key from ignition.
  4. Perform this step within 10 seconds. Insert new key to be registered in ignition.
  5. Perform this step within 10 seconds. Depress and release accelerator pedal one time. Security indicator should flash.
  6. After one minute, additional master key is registered. Security indicator should turn off. If programming additional keys, repeat process starting with step 4 . If additional keys do not need programming, remove master key from ignition. Depress and release brake pedal at least once after security indicator has been out for 10 seconds to complete registration mode.

ADDITIONAL SUB-KEY

Note. Additional sub-key may be registered by 2 different methods: using brake pedal and accelerator pedal, or using LEXUS scan tool. It is possible to register up to 3 sub-key codes including the already registered key code.

  1. Insert registered master key in ignition.
  2. Perform this step within 15 seconds. Depress and release accelerator pedal 4 times.
  3. Perform this step within 20 seconds. Depress and release brake pedal 5 times. Remove master key from ignition.
  4. Perform this step within 10 seconds. Insert new key to be registered in ignition.
  5. Perform this step within 10 seconds. Depress and release accelerator pedal one time. Security indicator should flash.
  6. After one minute, additional sub-key is registered. Security indicator should turn off. If programming additional keys, repeat process starting with step 4 . If additional keys do not need programming, remove master key from ignition. Depress and release brake pedal at least once after security indicator has been out for 10 seconds to complete registration mode.

ERASURE OF TRANSPONDER KEY CODE

Note. There are 2 different methods to erase the transponder key code: using brake pedal and accelerator pedal, or using LEXUS scan tool. All other master and sub-key codes are deleted leaving the master key code which was used when performing the operation. When using the ignition key which was used before deleting, it is necessary to register the code again.

  1. Insert master key in ignition.
  2. Perform this step within 15 seconds. Depress and release accelerator pedal 6 times.
  3. Perform this step within 20 seconds. Depress and release brake pedal 7 times. Security indicator should flash.
  4. Perform this step within 10 seconds. Remove master key. Security indicator should flash. 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 .

Using Jumper Wire

Turn ignition switch to ON position. Locate Data Link Connector 1 (DLC1) in engine compartment, in left rear corner, behind fuse/relay block. Using a fused jumper wire, connect Data Link Connector 1 (DLC1) terminal No. 11 (Tc) and terminal No. 3 (E1). (Scheme 9) Read Malfunction Indicator Light (MIL) in instrument cluster. If DTC 99 is retrieved, see TROUBLE SHOOTING SYMPTOMS table under TROUBLE SHOOTING. If any other DTCs are retrieved, see ENGINE IMMOBILIZER DTC DEFINITIONS table. Each DTC will be displayed in order, starting with lowest DTC. After checking DTCs, disconnect jumper wire to turn off display. Erase DTCs by disconnecting battery or removing EFI fuse.

DTCDefinition
B2785Ignition Switch On Malfunction
B2786Ignition Switch Off Malfunction
B2791Key Unlock Warning Switch Off Malfunction
B2795Unmatched Key Code
B2796No Communication In Immobilizer System
B2797Communication Malfunction No. 1
B2798Communication Malfunction No. 2

ENGINE IMMOBILIZER DTC DEFINITIONS

Scheme 9

Scheme 9

ECM PIN VOLTAGE TESTS

Turn ignition switch to ON position. Using a voltmeter, check voltage between specified terminals of ECM. (Scheme 10) See ECM TERMINAL VOLTAGE SPECIFICATIONS table. If voltage is not as specified, repair wiring harness or replace components as necessary. If voltages are as specified, replace ECM.

Check Voltage Between TerminalsVoltage
E9-18 (Green Wire) & E6-17 (Brown Wire)10-14
E9-19 (Purple Wire) & E6-17 (Brown Wire)10-14
E9-23 (Blue Wire) & E6-17 (Brown Wire)10-14
E9-28 (Violet Wire) & E6-17 (Brown Wire)10-14

ECM TERMINAL VOLTAGE SPECIFICATIONS

Scheme 10

Scheme 10

KEY UNLOCK WARNING SWITCH

Disconnect key unlock warning switch 2-pin connector (located in steering column, near ignition switch). With key in ignition, check continuity between switch terminals No. 1 and 2. Continuity should exist. With key removed from ignition, check continuity between terminals No. 1 and 2. Continuity should not exist. If continuity is not as specified, replace key unlock warning switch.

TRANSPONDER KEY COIL

Check continuity between transponder key coil terminals No. 1 and 2. If continuity does not exist, replace transponder key coil.