LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 2003 >> Tribute LX, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 26 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P0133: Ho2S (Front) Circuit, Slow Response >> Diagnosis & Repair Procedure

Diagnosis & Repair Procedure

WARNING: This page is about a different car, the 2002 Mazda Protege5 and 2002 Mazda Protege. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition off. Connect scan tool to DLC-2. Turn ignition on, engine off. Monitor for FREEZE FRAME DATA and ensure data has been recorded. Check service bulletins for repair information related to this DTC. If repair information is not available, go to next step. If repair information is available, perform diagnosis and repair as necessary. After repair, go to step  14.
  2. Turn ignition switch off and then start engine. Using scan tool, check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If any other DTCs are present with P0133, repair those DTCs first. If no other DTCs are present, are present, go to next step.
  3. Check if DTC P0133 is present in FREEZE FRAME DATA. If DTC is present, go to next step. If DTC is not present, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
  4. Start engine and warm up to normal operating temperature. Using scan tool, access FHO2S PID data. Depress accelerator pedal to Wide Open Throttle (WOT) and release to race engine. FHO2S PID reading should be more than .45 volt during acceleration (rich condition) and less than .45 volt during deceleration when fuel is cut (lean condition). If voltage is as specified, go to step  7. If voltage is not as specified, go to next step.
  5. Check front HO2S installation. If HO2S is installed properly, go to next step. If HO2S is loose, tighten HO2S and go to step  14.
  6. Check for exhaust leak upstream of front HO2S. If problem is found, repair or replace faulty exhaust parts as necessary and go to step  14. If no problem is found, replace front HO2S and go to step  14.
  7. Using scan tool, access LONGFT1 PIDs. Compare reading with FREEZE FRAME DATA in step  1. If LONGFT1 reading is less than FREEZE FRAME DATA value, engine is driven under rich condition. Go to next step. If LONGFT1 reading is more than FREEZE FRAME DATA value, engine is driven under lean condition. Go to
  8. Start engine, Check fuel line pressure while engine is running. See FUEL PRESSURE (EXCEPT B2300, B3000, B4000 & TIRBUTE) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURE article. If fuel line pressure is 30-36 psi, go to step  13. If fuel line pressure is not as specified, go to next step.
  9. Disconnect vacuum hose from fuel pressure regulator. Ensure vacuum is present at end of vacuum hose. If vacuum is present, inspect fuel pump maximum pressure and fuel return line for restriction. Repair or replace faulty parts as necessary. If all parts a okay, replace fuel pressure regulator and go to step  14. If vacuum is not felt at end of vacuum hose, ensure vacuum hoses are routed correctly. If vacuum hoses are okay, replace Pressure Regulator Control (PRC) solenoid valve. If vacuum hoses are not routed correctly, repair as necessary and go to step  14.
  10. Inspect fuel line pressure with engine running. See FUEL PRESSURE (EXCEPT B2300, B3000, B4000 & TIRBUTE) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURE article. If fuel pressure is 30-36 psi, go to step  13. If fuel pressure is not as specified, go to next step.
  11. Visually inspect fuel lines for leaks. If any fuel leaks are found, repair or replace fuel lines as necessary. If fuel leaks are not found, check fuel filters for clogging or foreign material. If problem is found at high or low pressure fuel filter, replace appropriate fuel filter. If no problems are found with fuel lines or filters, go to next step.
  12. Perform fuel pump maximum pressure test. FUEL PRESSURE (EXCEPT B2300, B3000, B4000 & TRIBUTE) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. If maximum fuel pressure is 64-92 psi, replace fuel pressure regulator and go to step  14. If maximum fuel pressure is not as specified, inspect fuel pump circuit for open or poor connection. If no problem is found with wire harness, replace fuel pump and go to step  14.
  13. Remove radiator cap. Start engine and allow to idle. Check cooling system for air bubbles or foaming coolant (combustion gases). If no problem is found, go to next step. If combustion gases are found in cooling system, repair leak and go to next step.
  14. Reconnect all connectors. Turn ignition switch on. Clear DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. Start engine. Perform DRIVE MODE 1 - PCM ADAPTIVE MEMORY  and DRIVE MODE 3 - HO2S, HO2S HEATER & TWC REPAIR VERIFICATION  . Stop vehicle and access ON-BOARD SYSTEM READINESS TEST MODE  to inspect DRIVE MODE completion status. Ensure Readiness Function Check (RFC) flag change from YES to OXYGEN SENSOR. If RFC flag does not change run DRIVE MODE again. Access DIAGNOSTIC MONITOR TEST RESULTS. Verify TESTs No. 10:01:11, 10:02:11 and 10:03:11 values. If TEST values are all below MAX value, go to next step. If TEST values are more than MAX value, replace PCM and go to next step.
  15. Cycle ignition switch from off to on. Check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. 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