LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 2002 >> Tribute LX, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 59 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P0057: Left Rear Ho2S Heater Circuit Low >> 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. Inspect Poor Connection Of HO2S (Left Rear) Connector -  Turn ignition off. Disconnect left rear HO2S 4-pin harness connector. Check for damaged, loose or corroded terminals. If problem is not present, go to next step. If problem is present, repair as necessary. After repair, go to step  8.
  3. Inspect HO2S Heater (Rear) -  Measure resistance between left rear HO2S terminals "C" and "D". See Figure. If resistance is 14.1-18.9 ohms, go to next step. If resistance is not 14.1-18.9 ohms, replace left rear HO2S. After repair, go to step  8.
  4. Inspect HO2S Heater (Left Rear) Power Circuit For Open -  Turn ignition on, engine off. Measure voltage in Black/White wire between ground and left rear HO2S 4-pin harness connector terminal "C". See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Black/White wire between left rear HO2S 4-pin harness connector terminal "C" and ignition switch. After repair, go to step  8.
  5. Inspect Poor Connection Of PCM Connector -  Turn ignition off. Disconnect PCM 104-pin harness connector. Check for damaged, loose or corroded terminals. If problem is not present, go to next step. If problem is present, repair as necessary. After repair, go to step  8.
  6. Inspect Control Circuit Of HO2S Heater (Left Rear) For Short To Ground -  Check continuity in Green/Orange wire between ground and left rear HO2S 4-pin harness connector terminal "D". If continuity is not present, go to next step. If continuity is present, repair short to ground in Green/Orange wire between left rear HO2S 4-pin harness connector terminal "D" and PCM 104-pin harness connector terminal No. 96. See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. After repair, go to step  8.
  7. Inspect HO2S Heater (Left Rear) Control Circuit For Open -  Connect 104-pin Breakout Box (49-UN01-130) to PCM harness connector only. Check continuity between left rear HO2S 4-pin harness connector terminal "B" and breakout box terminal No. 96. See Figure. If continuity is present, go to next step. If continuity is not present, repair open on Green/Orange wire between left rear HO2S harness connector terminal "B" and PCM harness connector terminal No. 96. After repair, go to next step.
  8. Verify Trouble Shooting Of DTC P0057 Completed -  Reconnect all connectors. Turn ignition on, engine off. Using scan tool, clear DTC from memory. See CLEARING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. Start engine. Check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC P0057 is present, replace PCM. After repair, go to next step. If DTC P0057 is not present, go to next step.
  9. 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