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Diagnostic Trouble Code Definitions

CAUTION: DO NOT crank engine before replacement PCM is programed to immobilizer system or PCM will be severely damaged. If test procedures require replacement of PCM on a vehicle equipped with immobilizer system, vehicle must be sent to an authorized Mazda dealer to have replacement PCM programed.
NOTE: Vehicle with immobilizer system can be identified by a solid urethane ignition key head.
NOTE: Before performing any diagnostic test, refer to WARNINGS, CAUTIONS and NOTES under DIAGNOSTIC TESTS .
DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC System Affected
P0010  Camshaft Actuator Circuit
P0011  Camshaft Timing Over-Advanced
P0012  Camshaft Timing Over-Retarded
P0031  Front Heated Oxygen Sensor Heater Control Circuit Low
P0032  Front Heated Oxygen Sensor Heater Control Circuit High
P0037  Rear Heated Oxygen Sensor Heater Control Circuit Low
P0038  Rear Heated Oxygen Sensor Heater Control Circuit High
P0101  Mass Airflow Sensor Circuit Range Performance Malfunction
P0102  Mass Airflow Sensor Circuit Low Input
P0103  Mass Airflow Sensor Circuit High Input
P0106  BARO Circuit Performance Problem
P0107  BARO Circuit Low Input
P0108  BARO Circuit High Input
P0111  Intake Air Temperature Sensor Circuit Performance Malfunction
P0112  Intake Air Temperature Sensor Circuit Low Input
P0113  Intake Air Temperature Sensor Circuit High Input
P0116  Engine Coolant Temperature Sensor Circuit Range/Performance Malfunction
P0117  Engine Coolant Temperature Sensor Circuit Low Input
P0118  Engine Coolant Temperature Sensor Circuit High Input
P0121 (3) Throttle Position Sensor Circuit Range/Performance Malfunction
P0122 (3) Throttle Position Sensor Circuit Low Input
P0123 (3) Throttle Position Sensor Circuit High Input
P0125  Insufficient Coolant Temperature For Closed Loop Fuel Control
P0126  Insufficient Coolant Temperature For Stable Operation
P0128  Coolant Temperature Less Than Thermostat Regulating Temperature
P0131  Front Heated Oxygen Sensor No Inversion - Low Voltage Stuck
P0132  Front Heated Oxygen Sensor No Inversion - High Voltage Stuck
P0133  Front Heated Oxygen Sensor Circuit Slow Response
P0134  Front Heated Oxygen Sensor Circuit No Activity Detected
P0138  Rear Heated Oxygen Sensor Circuit High Input
P0140  Rear Heated Oxygen Sensor Circuit No Activity Detected
P0171  Fuel Trim Too Lean
P0172  Fuel Trim System Too Rich
P0222 (5) Automatic Transmission
P0223 (5) Automatic Transmission
P0300 (2) Random Misfire Detected
P0301 (2) Cylinder No. 1 Misfire Detection
P0302 (2) Cylinder No. 2 Misfire Detection
P0303 (2) Cylinder No. 3 Misfire Detection
P0304 (2) Cylinder No. 4 Misfire Detection
P0327  Knock Sensor Circuit Low Input
P0328  Knock Sensor Circuit High Input
P0335  Crankshaft Position Sensor Circuit Malfunction
P0401  Exhaust Gas Recirculation System Insufficient Flow Detected
P0402  Exhaust Gas Recirculation System Excessive Flow Detected
P0403  Exhaust Gas Recirculation Valve Motor Coils - Open Or Short
P0420  Catalyst System Efficiency Below Threshold
P0441  EVAP Control System Incorrect Purge Flow
P0442  EVAP Control System Small Leak Detected
P0443 (1) EVAP Control System Purge Solenoid Valve Circuit Malfunction
P0446  Change Over Valve Stuck Closed
P0456  EVAP Control System Leak Detected - Small Leak
P0461  Fuel Gauge Sending Unit Circuit Range/Performance Problem
P0462  Fuel Gauge Sending Unit Circuit - Low Input
P0463  Fuel Gauge Sending Unit Circuit - High Input
P0480 (1) Cooling Fan Relay Circuit
P0500 (3) Vehicle Speed Sensor Malfunction
P0505  Idle Air Control Valve Circuit Malfunction
P0506  Idle Control System RPM Lower Than Expected
P0507  Idle Control System RPM Higher Than Expected
P0550  Power Steering Pressure Switch Circuit Malfunction
P0600  Communication Line Error - PCM/TCM
P0605 (1) Internal Control Module Read Only Memory Error
P0703  Brake Switch Input Circuit Malfunction
P0704  Clutch Switch Input Circuit Malfunction
P0705 (5) Automatic Transmission
P0706 (5) Automatic Transmission
P0715 (5) Automatic Transmission
P0720 (5) Automatic Transmission
P0725 (5) Automatic Transmission
P0741 (5) Automatic Transmission
P0742 (5) Automatic Transmission
P0743 (5) Automatic Transmission
P0751 (5) Automatic Transmission
P0752 (5) Automatic Transmission
P0753 (5) Automatic Transmission
P0756 (5) Automatic Transmission
P0757 (5) Automatic Transmission
P0758 (5) Automatic Transmission
P0850 (4) Neutral Switch Input Circuit Malfunction
P1487 (1) Exhaust Gas Recirculation Boost Sensor Solenoid Valve Circuit Malfunction
P1562  PCM +BB Voltage Low
P1602 (1) Immobilizer Unit-PCM Communication Line Error
P1603 (1) Key ID Number Unregistered In PCM
P1604 (1) Code Word Unregistered In PCM
P1608 (1) PCM Internal Circuit Malfunction
P1621 (1) Code Word Mismatch After Engine Cranking
P1622 (1) Key ID Number Mismatch
P1623 (1) Code Word Or Key Id Number Read/Write Error In PCM
P1624 (1) Immobilizer System Communication Counter = Zero
P1631 (1) Generator Output Voltage Signal No Electricity
P1633 (1) Battery Overcharge
P1634 (1) Generator Terminal "B" Circuit Open
P1740 (5) Automatic Transmission
P1742 (5) Automatic Transmission
P1751 (5) Automatic Transmission
P1752 (5) Automatic Transmission
P1756 (5) Automatic Transmission
P1757 (5) Automatic Transmission
P1771 (5) Automatic Transmission
P1772 (5) Automatic Transmission
P2004  Variable Tumble Control System Malfunction - Stuck Open
P2006  Variable Tumble Control System Malfunction - Stuck Closed
P2009  Variable Tumble Control System Solenoid Valve Circuit - Low Input
P2010  Variable Tumble Control System Solenoid Valve Circuit - High Input
P2401  EVAP System Leak Detection Pump Motor Circuit - Low Input
P2402  EVAP System Leak Detection Pump Motor Circuit - High Input
P2404  EVAP System Leak Detection Pump Air Filter Clogging
P2405  EVAP System Leak Detection Pump Orifice Fallen Off
P2406  EVAP System Leak Detection Pump Orifice Clogging
P2407  EVAP System Leak Detection Pump Heater Malfunction
(1) Malfunction Indicator Light (MIL) will not illuminate.
(2) Malfunction Indicator Light (MIL) should flash.
(3) Overdrive indicator light should flash.
(4) Testing is for M/T only. On A/T models. See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS.
(5) See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS.