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Home >> Mazda >> 2001 >> 626 LX, 2.5 D, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.5L >> Diagnostic Trouble Code Definitions
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Diagnostic Trouble Code Definitions

CAUTION: DO NOT crank engine before replacement PCM is programmed 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 programmed.
NOTE: Vehicle with immobilizer system can be identified by a solid urethane ignition key head.
DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC System Affected
P0102  Mass Airflow (MAF) Sensor Circuit, Low Input
P0103  Mass Airflow (MAF) Sensor Circuit, High Input
P0106  BARO Sensor Circuit, Performance Problem
P0107  BARO Sensor Circuit, Low Input
P0108  BARO Sensor Circuit, High Input
P0112  Intake Air Temperature (IAT) Sensor Circuit, Low Input
P0113  Intake Air Temperature (IAT) Sensor Circuit, High Input
P0116  Engine Coolant Temperature (ECT) Sensor Circuit, Performance Problem
P0117  Engine Coolant Temperature (ECT) Sensor Circuit, Low Input
P0118  Engine Coolant Temperature (ECT) Sensor Circuit, High Input
P0122  Throttle Position (TP) Sensor, Low Input
P0123  Throttle Position (TP) Sensor, High Input
P0125  Excessive Time To Enter Close Loop
P0133  Right Front Heated Oxygen Sensor Circuit, Slow Response
P0135  Right Front Heated Oxygen Sensor Heater Circuit Malfunction
P0136  Right Rear Heated Oxygen Sensor Circuit Malfunction
P0141  Right Rear Heated Oxygen Sensor Heater Circuit Malfunction
P0142  Rear Heated Oxygen Sensor Circuit Malfunction
P0147  Rear Heated Oxygen Sensor Heater Circuit Malfunction
P0153  Left Front Heated Oxygen Sensor Circuit, Slow Response
P0155  Left Front Heated Oxygen Sensor Heater Circuit Malfunction
P0161  Left Rear Heated Oxygen Sensor Heater Circuit Malfunction
P0171  Right Side Fuel Trim System, Too Lean
P0172  Right Side Fuel Trim System, Too Rich
P0174  Left Side Fuel Trim System, Too Lean
P0175  Left Side Fuel Trim System, Too Rich
P0230  Fuel Pump, Primary Circuit Malfunction
P0300 (1) Misfire Detection Monitor (Random)
P0301 (1) Misfire Cylinder No. 1 Misfire Detected
P0302 (1) Misfire Cylinder No. 2 Misfire Detected
P0303 (1) Misfire Cylinder No. 3 Misfire Detected
P0304 (1) Misfire Cylinder No. 4 Misfire Detected
P0305 (1) Misfire Cylinder No. 5 Misfire Detected
P0306 (1) Misfire Cylinder No. 6 Misfire Detected
P0320  Crankshaft Position (CKP) Sensor Circuit Malfunction
P0325  Knock Sensor (KS) Circuit Malfunction
P0340  Camshaft Position (CMP) Sensor Circuit Malfunction
P0400  EGR Flow Malfunction
P0420  Catalyst System Efficiency, Out Of Range, Low
P0421  Right Side Catalyst Warm-Up Efficiency, Low
P0431  Left Side Catalyst Warm-Up Efficiency, Low
P0442  Evaporative Emission System, Small Leak
P0443  Evaporative Emission System Purge Control Valve Circuit Malfunction
P0446  Evaporative Emission System Vent Control Malfunction
P0452  Evaporative Emission System Fuel Tank Pressure Sensor, Low Input
P0453  Evaporative Emission System Fuel Tank Pressure Sensor, High Input
P0455  Evaporative Emission System, Large Leak
P0460  Fuel Gauge Sender Unit Circuit Malfunction
P0461  Fuel Gauge Sender Unit Circuit, Performance Problem
P0500  Vehicle Speed Sensor (VSS) Circuit Malfunction
P0505  Idle Air Control (IAC) Valve, System Malfunction
P0603  Powertrain Control Module (PCM), Keep Alive Memory (KAM) Test Error
P0605  Powertrain Control Module Malfunction (PCM), Read Only Memory (ROM), Test Error
P0703  Brake Switch Malfunction
P0704 (2) Clutch Switch Circuit Malfunction
P0705 (3) Automatic Transmission
P0706 (3) Automatic Transmission
P0710 (3) Automatic Transmission
P0711 (3) Automatic Transmission
P0715 (3) Automatic Transmission
P0731 (3) Automatic Transmission
P0732 (3) Automatic Transmission
P0733 (3) Automatic Transmission
P0734 (3) Automatic Transmission
P0740 (3) Automatic Transmission
P0743 (3) Automatic Transmission
P0745 (3) Automatic Transmission
P0750 (3) Automatic Transmission
P0755 (3) Automatic Transmission
P0760 (3) Automatic Transmission
P1001  Data Link Connector (DLC) Malfunction
P1100  Mass Airflow (MAF) Sensor, Intermittent Malfunction
P1101  Mass Airflow (MAF) Sensor, Out Of Range
P1112  Intake Air Temperature (IAT) Sensor, Intermittent Malfunction
P1116  Engine Coolant Temperature (ECT) Sensor, Out Of Range
P1117  Engine Coolant Temperature (ECT) Sensor, Intermittent Malfunction
P1120  Throttle Position (TP) Sensor, Out Of Range (Low)
P1121  Throttle Position (TP) Sensor Inconsistent With Mass Airflow (MAF) Sensor
P1124  Throttle Position (TP) Sensor Inconsistent With RPM, Greater Than Expected
P1125  Throttle Position (TP) Sensor, Intermittent Problem
P1127  Cold Exhaust
P1130  Right Front Heated Oxygen Sensor Not Switching (Adapted Fuel Limit)
P1131  Right Front Heated Oxygen Sensor Not Switching (Sensor Indicates Lean)
P1132  Right Front Heated Oxygen Sensor Not Switching (Sensor Indicates Rich)
P1137  Right Rear Heated Oxygen Sensor Not Switching (Sensor Indicates Lean)
P1138  Right Rear Heated Oxygen Sensor Not Switching (Sensor Indicates Rich)
P1143  Rear Heated Oxygen Sensor Switching, Sensor Indicates Lean
P1144  Rear Heated Oxygen Sensor Switching, Sensor Indicates Rich
P1150  Left Front Heated Oxygen Sensor Not Switching (Adapted Fuel Limit)
P1151  Left Front Heated Oxygen Sensor Not Switching (Sensor Indicates Lean)
P1152  Left Front Heated Oxygen Sensor Not Switching (Sensor Indicates Rich)
P1157  Left Rear Heated Oxygen Sensor Switching, Sensor Indicates Lean
P1158  Left Rear Heated Oxygen Sensor Switching, Sensor Indicates Rich
P1250 (4) Fuel Pressure Regulator Control (PRC) Solenoid Valve, Circuit Malfunction
P1409  EGR Valve Control Circuit Malfunction
P1410  EGR Boost Sensor Solenoid Valve Stuck
P1450  Evaporative Control System Malfunction (Vacuum Leak)
P1451  Canister Drain Cut Valve (CDCV) Circuit Malfunction
P1460 (4) WOT A/C Control Circuit Malfunction
P1464 (4) A/C Demand Out Of Range
P1474 (4) Cooling Fan Control Circuit Malfunction
P1479 (4) Condenser Fan Control Circuit Malfunction
P1487 (4) EGR Boost Sensor Solenoid Valve Circuit Malfunction
P1501 (4) Vehicle Speed Sensor (VSS), Out Of Range
P1504  Idle Air Control (IAC) Valve Circuit Malfunction
P1506  Idle Control System, RPM Less Than Expected
P1507  Idle Control System, RPM Greater Than Expected
P1516  Neutral Switch Input Circuit Malfunction
P1602 (4) Immobilizer Unit, PCM Communication Error
P1603 (4) Code Word Not Registered In PCM
P1604 (4) Key ID Number Not Registered In PCM
P1621 (4) Code Word Does Not Match After Engine Cranking
P1622 (4) Key ID Number Does Not Match
P1623 (4) Code Word Or Key ID Number, Read/Write Error In PCM
P1624 (4) Immobilizer System Communication Counter = Zero
P1633  Powertrain Control Module (PCM) Keep Alive Memory (KAM) Circuit, Low Voltage
P1650 (4) Power Steering Pressure (PSP) Switch, Out Of Range
P1652  Power Steering Pressure (PSP) Switch, Failed On
P1703 (4) Brake Switch, Out Of Range
P1705 (3) Automatic Transmission
P1765 (3) Automatic Transmission
P1780 (3) Automatic Transmission
(1) Malfunction Indicator Light (MIL) should flash.
(2) Manual transmission only.
(3) See appropriate ELECTRONIC CONTROL article in AUTOMATIC TRANSMISSIONS.
(4) Malfunction Indicator Light (MIL) will not illuminate.