2001 Toyota 4Runner BaseFACTORY OEM SERVICE PROCEDURE

Diagnostic Trouble Code Definitions

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC (1) Description
B2785 (2) Ignition Switch On Malfunction
B2786 (2) Ignition Switch Off Malfunction
B2791 (2) Key Unlock Warning Switch Off
B2795 (2) Unmatched Key Code
B2796 (2) No Communication In Immobilizer System
B2797 (2) Communication Malfunction No. 1
B2798 (2) Communication Malfunction No. 2
P0100 (3) Mass Airflow Meter Circuit
P0101  Mass Airflow Meter Circuit Range/Performance
P0110 (3) Intake Air Temperature Sensor Circuit
P0115 (3) Engine Coolant Temperature Sensor Circuit
P0116  Engine Coolant Temperature Sensor Circuit Range/Performance
P0120 (3) Throttle Position Sensor Circuit
P0121  Throttle Position Sensor Circuit Range/Performance
P0125  Insufficient Coolant Temperature For Closed Loop Fuel Control
P0128  Thermostat Malfunction
P0136  Heated Oxygen Sensor Circuit
P0141 (3) Heated Oxygen Sensor Heater Circuit
P0171  System Too Lean
P0172  System Too Rich
P0300  Random Misfire Detected
P0301  Cylinder No. 1 Misfire Detected
P0302  Cylinder No. 2 Misfire Detected
P0303  Cylinder No. 3 Misfire Detected
P0304  Cylinder No. 4 Misfire Detected
P0305  Cylinder No. 5 Misfire Detected
P0306  Cylinder No. 6 Misfire Detected
P0325 (3) Knock Sensor No. 1 Circuit
P0330 (3) Knock Sensor No. 2 Circuit
P0335  Crankshaft Position Sensor Circuit
P0340  Camshaft Position Sensor Circuit
P0420  Catalyst System Efficiency Below Threshold
P0440  Evaporative Emission Control System
P0441  Incorrect EVAP Purge Flow
P0442  EVAP Leak Detected
P0446  EVAP Vent Control Malfunction
P0450  EVAP Pressure Sensor Circuit
P0451  EVAP Pressure Sensor Range/Performance
P0500  Vehicle Speed Sensor Circuit
P0505  Idle Control System Malfunction
P0710 (4) Transmission Fluid Temp. Sensor Malfunction
P0750 (4) Shift Solenoid Valve No. 1 Malfunction
P0753 (4) Shift Solenoid Valve No. 1 Electrical Malfunction
P0755 (4) Shift Solenoid Valve No. 2 Malfunction
P0758 (4) Shift Solenoid Valve No. 2 Electrical Malfunction
P0770 (4) Shift Solenoid Valve SL Malfunction
P0773 (4) Shift Solenoid Valve SL Electrical Malfunction
P1120  Accelerator Pedal Position Sensor Circuit
P1121  Accelerator Pedal Position Sensor Range/Performance
P1125  Throttle Control Motor Circuit
P1126  Magnetic Clutch Circuit
P1127  Electronic Throttle Control System Actuator Power Source Circuit
P1128  Throttle Control Motor Lock Malfunction
P1129  Electronic Throttle Control Malfunction
P1130  Air/Fuel Sensor Circuit Range/Performance
P1133  Air/Fuel Sensor Circuit Response Malfunction
P1135  Air/Fuel Sensor Heater Circuit Malfunction
P1300 (3) Ignitor Circuit
P1335 (5) Crankshaft Position Sensor Circuit
P1520  Stoplight Switch Signal Circuit
P1600  Engine Control Module BATT Circuit
P1633  ECM Malfunction (Electronic Throttle Control System Circuit)
P1700 (4) Vehicle Speed Sensor No. 2 Malfunction
P1760 (4) Shift Solenoid Valve SLT Malfunction
P1780  Park/Neutral Position Switch Circuit
(1) Some DTCs are two-trip detection logic DTCs. For more information, see TWO-TRIP DETECTION LOGIC  under SELF-DIAGNOSTIC SYSTEM.
(2) DTC applies to models equipped with engine immobilizer system. MIL will not illuminate if DTC exists. For testing procedures, see appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT.
(3) If this DTC is set, Engine Control Module (ECM) will enter fail-safe mode.
(4) DTC applies to electronically controlled automatic transmission. For testing procedures, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
(5) MIL will not illuminate.
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  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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