Engine ECU Diagnostic Trouble Codes

Engine ECU - SAE Controlled

These items are taken from the table "Engine Diagnostics, SAE controlled" on pages DI-14 to DI-16 in the Engine Diagnostics chapter of the Repair Manual.

P0100 - Mass Air Flow Circuit Malfunction

P0101 - Mass Air Flow Circuit Range/Performance Problem

P0110 - Intake Air Temp Circuit Malfunction

P0115 - Engine Coolant Temp. Circuit Malfunction

P0116 - Engine Coolant Temp. Circuit Range/Performance Problem

P0120 - Throttle/Pedal Position Sensor/Switch "A" Circuit Malfunction

P0121 - Throttle/Pedal Position Sensor/Switch "A" Circuit Range/Performance Problem

P0125 - Insufficient Coolant Temp. for Closed Loop Fuel Control

P0128 - Thermostat Malfunction

P0130 - Heated Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 1) (Except Calif.)

P0133 - Oxygen Sensor Circuit Slow Response (Bank 1 Sensor 1)

P0135 - Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 1)

P0136 - Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 2)

P0141 - Oxygen Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)

P0171 - System too Lean (Fuel Trim)

P0172 - System too Rich (Fuel Trim)

P0300 - Random/Multiple Cylinder Misfire Detected

P0301 - Cylinder 1 Misfire Detected

P0302 - Cylinder 2 Misfire Detected

P0303 - Cylinder 3 Misfire Detected

P0304 - Cylinder 4 Misfire Detected

P0325 - Knock Sensor 1 Circuit Malfunction (Bank 1)

P0335 - Crankshaft Position Sensor "A" Circuit Malfunction

P0340 - Camshaft Position Sensor Circuit Malfunction

P0420 - Catalyst System Efficiency Below Threshold (Bank 1)

P0440 - Evaporative Emission Control System Malfunction

This and the following two DTCs can occur if you drive around for a while with a loose fuel filler cap. I did this to test retreiving DTCs with the Prius Mini-Scanner and it took more than a day for the problem to be detected.

P0441 - Evaporative Emission Control System Incorrect Purge Flow

P0446 - Evaporative Emission Control System Vent Control Malfunction

P0450 - Evaporative Emission Control System Pressure Sensor Malfunction

P0451 - Evaporative Emission Control System Pressure Sensor Range/Performance

P0500 - Vehicle Speed Sensor Malfunction

P0505 - Idle Control System Malfunction

Engine ECU - Manufacturer Controlled

These items are taken from the table "Engine Diagnostics, manufacturer controlled" on pages DI-17 and DI-18 in the Engine Diagnostics chapter of the Repair Manual.

P1125 - Throttle Control Motor Circuit Malfunction

P1127 - ETCS Actuator Power Source Circuit Malfunction

P1128 - Throttle Control Motor Lock Malfunction

P1129 - Electric Throttle Control System Malfunction

P1300 - Igniter Circuit Malfunction (No. 1)

P1305 - Igniter Circuit Malfunction (No. 2)

P1310 - Igniter Circuit Malfunction (No. 3)

P1315 - Igniter Circuit Malfunction (No. 4)

P1346 - VVT Sensor/Camshaft Position Sensor Circuit Range/Performance Problem (Bank 1)

P1349 - VVT System Malfunction (Bank 1)

P1430 - Vacuum Sensor for Adsorber and Catalyst System Circuit Malfunction

P1431 - Vacuum Sensor for Adsorber and Catalyst System Circuit Range/Performance Problem