P0133
DTC P0133 HO2S CIRCUIT SLOW RESPONSE (BANK 1 / SENSOR 1)Component Location:
COMPONENT LOCATION
GENERAL DESCRIPTION
The HO2S is used to supply the PCM with information regarding the composition of the air/fuel mixture. The HO2S is positioned in the exhaust pipe ahead of the TWC. To measure the oxygen content, the HO2S requires a supply of ambient air as a reference. The HO2S produces a voltage that varies between 0.1 V and 0.9 V under normal operating conditions. The Powertrain Control Module (PCM) monitors this voltage and determines if the exhaust gas is lean or rich. If the voltage input at the PCM is under approx. 0.45 V the exhaust is lean, and if the voltage input is over approx. 0.45 V the exhaust is rich. The PCM constantly monitors the HO2S signal during closed loop operation and compensates for a rich or lean condition by decreasing or increasing injector pulse width as necessary.
DTC DESCRIPTION
If the HO2S signal's response time from lean to rich(from rich to lean) is longer than 1.3(0.8) seconds, the PCM judged as a fault and DTC is set.
DTC Detecting Condition:
DTC DETECTING CONDITION
Specification:
SPECIFICATION
Schematic Diagram:
SCHEMATIC DIAGRAM
Signal Waveform & Data:
SIGNAL WAVEFORM & DATA
MONITOR SCANTOOL DATA
1. Connect Scantool & Engine "ON".
2. Warm up the engine to normal operating temperature.
3. Monitor HO2S voltage(B1/S1) parameter on scantool.
Specification : Verify that signal is varying from rich (above 0.45 V) to lean (below 0.45 V) a minimum of 3 times in 10 seconds (Voltage will vary between 0.1 and 0.9 V )
4. Is the HO2S parameter displayed within specifications ?
YES: Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection,bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "Component Inspection" procedure.
COMPONENT INSPECTION
1. Visual Inspection of HO2S
1. Visually/physically inspect following items:
- Inspect the front HO2S for Contaminated, deteriorated or aged Front HO2S.
- If contamination is evident on the HO2S, replace contaminated sensor.
2. Is the HO2S visually / physically O.K ?
YES: Go to "Check Performance of HO2S" as below.
NO: Substitute with a known - good HO2S and check for proper operation.
If the problem is corrected, replace HO2S and go to "Verification of Vehicle Repair" procedure.
2. Check performance of HO2S.
1. Connect scantool & Engine "ON"
2. Warm-up the engine to normal engine temperature.
3. Monitor signal waveform of HO2S and 02 sensor Test Result in 08 CARB OBD-II DIAGNOSIS with scantool
Specification : Response times : lean to rich (Less than 1.2 sec) & from rich to lean (Less than 0.5 sec)
4. Is the sensor switching properly ?
YES: Go to "Check PCM" as below.
NO: Substitute with a known - good HO2S and check for proper operation.
If the problem is corrected, replace HO2S and go to "Verification of Vehicle Repair" procedure.
3. Check PCM
1. Ignition "OFF".
2. Connect Scantool and ignition"ON " & Engine "OFF".
3. Select simulation function on scantool.
4. Simulate voltage at terminal "1" of H02 sensor signal connector.
5. Does the H02 sensor signal value changes according to simulation voltage ?
YES: Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Substitute with a known - good PCM and check for proper operation.
If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code(DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all rediness test have been verified as "Complete"
5. Are any DTCs present ?
YES: Go to the applicable troubleshoooting procedure.
NO: System is performing to specification at this time.