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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 authorized Mazda dealer to have replacement PCM programed.
NOTE: Vehicle with immobilizer system can be identified by a solid urethane ignition key head.
DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC System Affected
P0100  MAF Circuit Malfunction
P0110  IAT Circuit Malfunction
P0115  Engine Coolant Temperature (ECT) Circuit Malfunction
P0120 (1) Throttle Position (TP) Circuit Malfunction
P0125  Insufficient Coolant Temperature For Closed Loop Fuel Control
P0130  Right Front HO2S Circuit Malfunction
P0134  Right Front HO2S Circuit, No Activity Detected
P0135  Right Front HO2S Heater Circuit Malfunction
P0140  Right Rear HO2S Circuit, No Activity Detected
P0141  Right Rear HO2S Heater Circuit Malfunction
P0150  Left Front HO2S Circuit Malfunction
P0154  Left Front HO2S Circuit, No Activity Detected
P0155  Left Front HO2S Heater Circuit Malfunction
P0160  Left Rear HO2S Circuit, No Activity Detected
P0161  Left Rear HO2S Heater Circuit Malfunction
P0170  Right Bank Fuel Trim Malfunction
P0173  Left Bank Fuel Trim Malfunction
P0300 (2) Random Misfire Detected
P0301 (2) Cylinder No. 1 Misfire Detected
P0302 (2) Cylinder No. 2 Misfire Detected
P0303 (2) Cylinder No. 3 Misfire Detected
P0304 (2) Cylinder No. 4 Misfire Detected
P0305 (2) Cylinder No. 5 Misfire Detected
P0306 (2) Cylinder No. 6 Misfire Detected
P0325  Knock Sensor Circuit Malfunction
P0335 (1) CKP Sensor Circuit Malfunction
P0400  EGR System Malfunction
P0404  EGR Circuit, Range/Performance Problem
P0421  Right Bank Catalyst System Efficiency Below Threshold
P0431  Left Bank Catalyst System Efficiency Below Threshold
P0442  EVAP Control System, Small Leak Detected
P0443 (3) EVAP Control System Purge Control Valve Circuit Malfunction
P0450  Fuel Tank Pressure Sensor Circuit Malfunction
P0451  Fuel Tank Pressure Sensor, Performance Problem
P0455  EVAP Control System, Excessive Leak Or Blockage Detected
P0464  Fuel Gauge Sending Unit Circuit, Slosh Check
P0480 (3) Condenser Fan Relay No. 1 Circuit Malfunction
P0481 (3) Cooling Fan Relay & Condenser Fan Relay No. 2 Circuit Malfunction
P0482 (3) Cooling Fan Relay & Condenser Fan Relay No. 2 Circuit Malfunction
P0500  Vehicle Speed Sensor Circuit Malfunction
P0505  Idle Air Control System Malfunction
P0550  Power Steering Pressure Switch Circuit Malfunction
P0703  Brake Switch Input Malfunction
P0705 (4) Automatic Transmission
P0706 (4) Automatic Transmission
P0710 (4) Automatic Transmission
P0711 (4) Automatic Transmission
P0715 (4) Automatic Transmission
P0731 (4) Automatic Transmission
P0732 (4) Automatic Transmission
P0733 (4) Automatic Transmission
P0734 (4) Automatic Transmission
P0740 (4) Automatic Transmission
P0745 (4) Automatic Transmission
P0750 (4) Automatic Transmission
P0755 (4) Automatic Transmission
P0760 (4) Automatic Transmission
P1170  Right Front HO2S, No Inversion
P1173  Left Front HO2S, No Inversion
P1195  BARO Circuit Malfunction
P1196  Starter Signal Circuit Malfunction
P1250 (3) PRC Solenoid Valve Circuit Malfunction
P1345  CMP Sensor Circuit Malfunction
P1402  EGR Valve Position Sensor Circuit Malfunction
P1449 (3) Canister Drain Cut Valve (CDCV) Circuit Malfunction
P1450  EVAP Control System Malfunction, Excessive Vacuum
P1455  Fuel Gauge Sender Unit Circuit Malfunction
P1487 (3) EGR Boost Sensor Solenoid Valve Circuit Malfunction
P1521 (3) Variable Resonance Induction System (VRIS) Solenoid Valve No. 1 Circuit Malfunction
P1522 (3) Variable Resonance Induction System (VRIS) Solenoid Valve No. 2 Circuit Malfunction
P1608  PCM Circuit Malfunction
P1609  PCM Internal Malfunction
P1627  Powertrain Control Module (PCM) - Anti-Lock Brake System (ABS)/Traction Control System (TCS) Line Communication Error
P1743 (4) Automatic Transmission
P1765 (4) Automatic Transmission
P1794  PCM +BB Voltage Low
(1) HOLD indicator light should flash.
(2) Malfunction Indicator Light (MIL) should flash or illuminate.
(3) Malfunction Indicator Light (MIL) will not illuminate.
(4) See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.