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CHECK Mode Code Retrieval (Lexus Scan Tool Only)

WARNING: This page is about a different car, the 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ensure vehicle battery is fully charged (at least 11 volts). Apply parking brake. Shift transmission/transaxle into Neutral (M/T) or Park (A/T). Turn A/C and all accessories off. Ensure throttle is in idle position.
  2. Turn ignition off. Connect scan tool to Data Link Connector (DLC) No. 3. See Figure. DLC No. 3 connector is located under left side of instrument panel. Turn ignition on with engine off. Turn scan tool on.
  3. Switch scan tool from NORMAL mode to CHECK mode. CHECK mode is operational if MIL on instrument cluster flashes. Start engine. Ensure MIL goes off. Try to simulate conditions of driveability complaint described by customer.
    NOTE: If ignition is turned from ON to ACC or OFF position, all DTCs and freeze-frame data will be erased. DO NOT switch modes until all DTCs and freeze-frame data are recorded.
  4. Record any DTCs and freeze-frame data displayed for system diagnosis. If driveability problem exists and no codes are present, go to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom.
  5. If any DTCs are present, perform appropriate circuit test. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION  table. For more information on freeze-frame data, see FREEZE-FRAME DATA  under INTRODUCTION. For information on 2-trip detection logic codes, see TWO-TRIP DETECTION LOGIC  under DETECTION LOGIC under INTRODUCTION.
  6. After repairs for DTC have been completed, DTC must be cleared from ECM memory. See CLEARING DIAGNOSTIC TROUBLE CODES .
    DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

    DTC (1) Description
    P0100  Mass Airflow (MAF) Sensor Circuit
    P0101  Mass Airflow (MAF) Sensor Circuit Range/Performance Fault
    P0110  Intake Air Temperature (IAT) Sensor Circuit
    P0115  Engine Coolant Temperature (ECT) Sensor Circuit
    P0116  Engine Coolant Temperature (ECT) Circuit Range/Performance Fault
    P0120  Throttle (TP)/Pedal Position Sensor Switch "A" Circuit Malfunction
    P0121  Throttle (TP)/Pedal Position Sensor Switch "A" Circuit Range/Performance Fault
    P0125  Insufficient Coolant Temperature For Closed Loop Fuel Control
    P0128  Thermostat Malfunction
    P0136  Heated Oxygen Sensor Circuit Fault (Bank 1 Sensor 2)
    P0141  Heated Oxygen Sensor Heater Circuit Fault (Bank 1 Sensor 2)
    P0171  System Too Lean (Fuel Trim - Bank 1)
    P0172  System Too Rich (Fuel Trim - Bank 1)
    P0174  System Too Lean (Fuel Trim - Bank 2)
    P0175  System Too Rich (Fuel Trim - Bank 2)
    P0300  Random Cylinder Misfire Detected
    P0301-P0306  Cylinders No. 1-6 Misfire Detected
    P0325/P0330  Knock Sensor Circuit Fault
    P0335  Crankshaft Position (CKP) Sensor Circuit
    P0340  Variable Valve Timing (VVT) Sensor Circuit
    P0420  Catalyst System Efficiency Below Threshold
    P0440  EVAP System Malfunction
    P0441  Incorrect EVAP Purge Flow
    P0442  EVAP System Small Leak Detected
    P0446  EVAP Vent Control Fault
    P0450  EVAP Pressure Sensor Malfunction
    P0451  EVAP Pressure Sensor Range/Performance Fault
    P0500  Vehicle Speed Sensor (VSS) Malfunction
    P0505  Idle Control System Malfunction
    P0710(2) Transmission Fluid Temperature Sensor Fault
    P0750(2) Shift Solenoid Valve No. 1 Fault
    P0753(2) Shift Solenoid Valve No. 1 Electrical Fault
    P0755(2) Shift Solenoid Valve No. 2 Fault
    P0758(2) Shift Solenoid Valve No. 2 Electrical Fault
    P0765(2) Shift Solenoid Valve No. 4 Fault
    P0768(2) Shift Solenoid Valve No. 4 Electrical Fault
    P0770(2) Lock-Up Solenoid Fault
    P0773(2) Lock-Up Solenoid Circuit Electrical Fault
    P1130/P1150  Air/Fuel Sensor Circuit Range/Performance Fault
    P1133/P1153  Air/Fuel Sensor Circuit Response Malfunction
    P1135/P1155  Air/Fuel Sensor Heater Circuit Malfunction
    P1300, P1305, P1310, P1315, P1320 Or P1325  Ignitor Circuit Malfunction
    P1335  Crankshaft Position (CKP) Sensor Circuit
    P1346/P1351  Variable Valve Timing (VVT) Circuit Range/Performance Fault
    P1349/P1354  Variable Valve Timing (VVT) System Malfunction
    P1350  Variable Valve Timing (VVT) Circuit Malfunction
    P1520  Stoplight Switch Signal Malfunction
    P1600  ECM Batt Malfunction
    P1656/P1663  Oil Control Valve (OCV) Malfunction
    P1725(2) Input Turbine Speed Sensor Circuit Fault
    P1730(2) Counter Gear Speed Sensor Circuit Fault
    P1760(2) Shift Solenoid Valve SLT Fault
    P1780  Park/Neutral Position Switch Malfunction
    B2795(3) Unmatched Key Code
    B2796(3) No Communication In Immobilizer System
    B2797(3) Communication Malfunction No. 1
    B2798(3) Communication Malfunction No. 2
    (1) Some codes are two-trip detection logic code(s). For more information, see DETECTION LOGIC  under INTRODUCTION.
    (2) These codes only apply to electronically controlled transmissions. For testing procedures, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
    (3) MIL will not illuminate. For testing procedures, see ENGINE IMMOBILIZER SYSTEMS - RX300 article in ACCESSORIES & EQUIPMENT.
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