LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 2013 >> 5 Grand Touring >> Repair and Diagnosis >> External Pages >> Different car >> Section 57 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P0172 Or DTC P0175 >> Diagnostic Procedures

Diagnostic Procedures

WARNING: This page is about a different car, the 2003 Mazda MPV and 2002 Mazda MPV. However, it is still accessible from the selected car via links, so may be relevant.
  1. Record freeze frame data. Check for service bulletins and on-line information. Repair as necessary. After repair, go to next step.
  2. Verify Related Pending Code Or Stored DTCs -  Turn ignition on, engine off. Using scan tool, verify related pending code or stored DTCs. If any other DTC is present, repair that DTC first. Refer to DIAGNOSTIC TROUBLE CODE IDENTIFICATION . If other DTCs or driveability problems are not present, go to next step. If no other DTCs are present and driveability problems are present, go to step  8.
  3. Identify Trigger DTC For FREEZE FRAME DATA -  If DTC P0172 or P0175 are present in FREEZE FRAME DATA, go to next step. If DTCs P0172 or P0175 are not present in FREEZE FRAME DATA, go to diagnostic procedure for DTC that is on FREEZE FRAME DATA. Refer to DIAGNOSTIC TROUBLE CODE IDENTIFICATION .
  4. Verify Current Input Signal Status (Ignition Key To On/Idle) -  Using scan tool, access MAF, ECT, TP and VSS PIDs with ignition on and engine running. Compare readings with specifications. See PIN VOLTAGE/PID VALUE CHARTS article. If all data is within specification, go to next step. If any data is not within specification with ignition on and engine runs, inspect suspect sensor and related wire harness for excessive resistance. Refer to appropriate test in SYSTEM & COMPONENT TESTING - MAZDA6, MIATA, MPV, PROTEGE & PROTEGE5 article. After repair, go to step  10.
  5. Verify Current Input Signal Status Under Trouble Condition -  Referring to FREEZE FRAME DATA, operate vehicle under same conditions as when DTC was set. Check PID data for MAF, ECT, TP and VSS. Compare readings with specifications. See PIN VOLTAGE/PID VALUE CHARTS in PIN VOLTAGE CHARTS article. If all data is within specification, go to next step. If any input causes drastic changes, inspect suspected sensor and related wire harnesses. Refer to appropriate test in SYSTEM & COMPONENT TESTING - MAZDA6, MIATA, MPV, PROTEGE & PROTEGE5 article. Repair or replace as necessary. After repair, go to step  10.
  6. Verify Current Input Signal Status Of Front HO2S -  Using scan tool, access O2S11 for P0172 or O2S21 for P0175 PID. Verify PID while racing engine in park or neutral. If PID reading is more than 0.45 volt when suddenly depress accelerator pedal (rich condition) and less than 0.45 volt just after release of accelerator pedal (lean condition), go to next step. If PID reading is not as specified, replace suspect front HO2S. After repair, go to step  10.
  7. Inspect Fuel Line Pressure -  Turn ignition off. Connect fuel gauge to fuel pipe. Start engine and run at idle. Check fuel line pressure. See FUEL PRESSURE (EXCEPT B2300, B3000, B4000 & TRIBUTE) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. If pressure is 61-66 psi (420-460 kPa), go to next step. If fuel line pressure is not as specified, check fuel pump maximum pressure and fuel return hose for clogging. If problem is present, repair as necessary. If problem is not present, replace fuel pressure regulator. After repair, go to step  10.
  8. Inspect Long Term Fuel Trim -  Turn ignition off. Disconnect purge hose from intake manifold. Plug end of hose and intake manifold port. Using scan tool, access LONGFT1 (P0172) or LONGFT2 (P0175) PIDs. Start engine and warm up to normal operating temperature. If PID reading does not change to positive value, go to next step. If PID reading changes to a positive value, inspect purge solenoid valve. See FUEL EVAPORATIVE SYSTEM (MPV) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING - MAZDA6, MIATA, MPV, PROTEGE & PROTEGE5 article. Repair as necessary. After repair, go to step  10.
  9. Inspect PCV Valve Operation -  Check PCV valve operation. See POSITIVE CRANKCASE VENTILATION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING - MAZDA6, MIATA, MPV, PROTEGE & PROTEGE5 article. If PCV valve is okay, go to next step. If PCV valve is faulty, replace PCV valve. After repair, go to next step.
  10. Verify Trouble Shooting Of DTC P0172 Or P0175 Completed -  Reconnect all components. Turn ignition on, engine off. Using scan tool, clear DTC. See CLEARING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. Start engine and perform MODE 1 - PCM ADAPTIVE MEMORY PRODUCE DRIVE MODE  and MODE 3 - HO2S HEATER, HO2S & TWC REPAIR VERIFICATION DRIVE MODE  under DRIVE MODES. Stop vehicle and access PID/DATA MONITOR RECORDED to inspect DRIVE MODE completion status. Ensure Readiness Function Check (RFC) flag changes to OFF for FUEL SYSTEM MONITOR. If RFC flag does not change, run DRIVE MODE again. Access PENDING CODE. If no DTC is present, go to next step. If same DTC is present, replace PCM. After repair, go to next step.
  11. Verify After Repair Procedure -  Using scan tool, perform After Repair Procedure. See AFTER REPAIR PROCEDURE . If no other DTCs are present, testing is complete. If any other DTC is present, go to applicable test and repair.
scientia non olet · About LEMON Manuals