P0133
P0133-O2 SENSOR 1/1 SLOW RESPONSE
Special Tools:
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The wide-band O2 Sensor operates differently than traditional O2 Sensors. The wide-band O2 Sensor tip consists of two cells that provide different functions, a measurement chamber and a detection chamber with pumping capabilities. The oxygen pumping function is the ability to pump oxygen into or out of the measurement chamber depending on the level of oxygen in the measurement chamber. This function provides the wide-band sensing capabilities and is critical for proper oxygen measurement. The O2 Sensor Reference circuit provides a common bias supply to both the O2 Sensor Signal and the O2 Sensor Pump Cell Current circuits.
During normal operation, the O2 Sensor Reference voltage and O2 Sensor Signal voltage will be a fixed voltage value. The O2 Sensor Current Pump voltage will switch from between 0.45 volts above and below the fixed O2 Sensor Return voltage, allowing current to flow in either direction through the pump. This correlates with the pumping of oxygen into and out of the measurement chamber. On a properly operating vehicle, this happens very quickly and the voltage reading should maintain a steady 0.45 volts when taking a voltage measurement between the O2 Sensor Signal circuit and the O2 Sensor Reference circuit of the O2 Sensor with the engine running and the O2 Sensor operating in closed loop.
When the exhaust stream has a lean air/fuel ratio (high oxygen content) the pumping element voltage will move toward +0.45 volts pumping oxygen out of the measurement chamber. When the exhaust stream has a rich air/fuel ratio (relatively low oxygen content) the pumping element voltage will move toward -0.45 volts pumping oxygen into the measurement chamber.
- When Monitored:
All of the following conditions must be met for the monitor to run; 1. With the engine running for more than 30 seconds; 2. Monitor has not run during this cycle; 3. Engine Coolant Temperature (ECT) Sensor reading between 65°C (149°F) and 125°C (257°F); 4. Engine between 1400 and 2900 RPM, vehicle speed between 48.3 kph (30 mph) and 115 kph (71.5 mph); 5. Engine load between 22 and 85%; 6. O2 Sensor in closed loop operation. Monitor will run once ignition cycle for 30 seconds.
- Set Condition:
The Powertrain Control Module (PCM) detects that the oxygen sensor signal does not switch adequately during monitoring. Two Trip Fault. Three good trips to turn off the MIL.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
Diagnostic Test
1. ACTIVE DTC
NOTE: After the repairs have been made, verify proper O2 Sensor operation. If all the O2 Sensor voltage readings have not returned to normal, follow the diagnostic procedure for the remaining O2 Sensors.
1. Start the engine.
2. Allow the engine to reach normal operating temperature.
WARNING:
When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
3. With a scan tool, read the active DTCs.
NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.
Is the DTC Active or Pending at this time?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.
2. CHECK THE O2 SENSOR VOLTAGE READINGS
NOTE: This DTC will set due to poor engine performance as well as a faulty O2 Sensor. If the vehicle exhibits any fuel system or driveability issues, or has any other driveability DTCs present, repair those concerns before proceeding with this test.
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/1 harness connector.
3. Connect the Wide-band O2 Sensor Diagnostic Adaptor 10367 in-line of the O2 Sensor 1/1 harness connector.
4. Start the engine and bring the engine speed up to 2500 RPM.
5. With the engine steady at 2500 RPM, measure the voltage:
- at the (K41) O2 Sensor Signal circuit at the appropriate terminal of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
- at the (K902) O2 Sensor Return circuit at the appropriate terminal of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
- at the (K89) O2 Sensor Pump Current circuit at the appropriate terminal of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
- between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit at the appropriate terminals of the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool.
NOTE: If the Powertrain Control Module detects an active open or short on any of the O2 Sensor 1/1 circuits, it will power down all of the O2 Sensor circuits to protect the O2 Sensor and PCM internal ASIC from being damaged.
6. If the O2 Sensor is powered up by the PCM and operating normal, the voltage readings should be as follows;
- The voltage at the (K41) O2 Sensor Signal circuit should be approximately 4.3 volts.
- The voltage at the (K902) O2 Sensor Return circuit should be approximately 3.85 volts.
- The voltage at the (K89) O2 Sensor Pump Current circuit should be switching between approximately 3.4 volts and 4.3 volts.
- The voltage between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit should switch between +0.45 volts and -0.45 volts.
NOTE: The voltage readings may vary up or down slightly depending on the age of the O2 Sensor and operating conditions of the engine. However, if the engine and O2 Sensor are operating normal the voltage reading between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit should switch between +0.45 volts and -0.45 volts with very little or no change.
Do the circuit voltages read as described?
Yes
- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.
No, voltage readings are at or near 0.0 volts
- Go To 3
No, voltage reading between the (K89) O2 Sensor Pump Current circuit and the (K902) O2 Sensor Return circuit is not switching between +0.45 volts and -0.45 volts
- Go To
3. CHECK THE (F343) FUSED ASD RELAY OUTPUT VOLTAGE
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/1 harness connector.
3. Remove the Wide-band O2 Sensor Diagnostic Adaptor 10367 tool. Leave the O2 Sensor 1/1 harness connector disconnected.
4. Turn the ignition on.
5. Measure the voltage on the (F343) Fused ASD Relay Output circuit at the O2 Sensor 1/1 harness connector.
Does the voltage read battery voltage?
Yes
- Go To 5
No
- Repair the (F343) Fused ASD Relay Output circuit for an open or short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
4. CHECK THE O2 SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
1. Measure for voltage at the:
- (K41) O2 Sensor 1/1 Signal circuit at the O2 Sensor 1/1 harness connector.
- (K902) O2 Sensor 1/1 Return circuit at the O2 Sensor 1/1 harness connector.
- (K89) O2 Sensor 1/1 Positive Current Control circuit at the O2 Sensor 1/1 harness connector.
NOTE: With the O2 Sensor disconnected, the PCM will power down the O2 Sensor and there should be no voltage on the circuits.
Do any of the circuits measure above 0.5 volts?
Yes
- Repair the circuit that measured above 0.5 volts for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 5
5. CHECK THE O2 SENSOR CIRCUITS FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the PCM C1 harness connector.
3. Measure the resistance between ground and the:
- (K41) O2 Sensor 1/1 Signal circuit at the O2 Sensor 1/1 harness connector.
- (K902) O2 Sensor 1/1 Return circuit at the O2 Sensor 1/1 harness connector.
- (K89) O2 Sensor 1/1 Current Pump Control circuit at the O2 Sensor 1/1 harness connector.
- (K79) O2 Sensor 1/1 Heater Control circuit at the O2 Sensor 1/1 harness connector.
Is the resistance above 10k Ohms between each of the above circuits and ground?
Yes
- Go To 6
No
- Repair the circuit that measured above below 10k Ohms for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
6. CHECK THE O2 SENSOR CIRCUITS FOR AN OPEN OR HIGH RESISTANCE
1. Measure the resistance of the:
- (K41) O2 Sensor 1/1 Signal circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
- (K902) O2 Sensor 1/1 Return circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
- (K89) O2 Sensor 1/1 Current Pump Control circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
- (K79) O2 Sensor 1/1 Heater Control circuit between the O2 Sensor 1/1 harness connector and the PCM C1 harness connector.
Is the resistance below 5.0 Ohms for each of the above circuits?
Yes
- Go To 7
No
- Repair the circuit that measured above 5.0 Ohms for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
7. O2 SENSOR
1. Replace the Oxygen Sensor and reconnect the harness connector. .
2. Turn the ignition on.
3. Start the engine.
4. Allow the engine to reach normal operating temperature.
WARNING:
When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
5. With a scan tool, read the active DTCs.
NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.
Did the DTC return?
Yes
- Replace the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
8. CHECK THE O2 SENSOR PUMPING CURRENT
1. With the scan tool, navigate to data display and monitor or the graph the O2 Sensor pump reading with the engine at 2500 RPM.
NOTE: The O2 pump current should cycle between +0.12 mA and -0.12 mA if there are no fuel or ignition system issues.
Follow the appropriate result below:
The current is cycling more positive in relation to zero indicating a lean condition
- Go To 9
The current is cycling more negative in relation to zero indicating a rich condition
- Go To 11
9. CHECKING THE INTAKE SYSTEM
1. Perform a check of the intake system for leaks or restrictions.
Were any problems found?
Yes
- Perform the appropriate repairs.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 10
10. CHECKING THE EXHAUST SYSTEM FOR LEAKS
1. Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS test procedure. Checking The Exhaust System For Leaks.
Were any exhaust leaks found?
Yes
- Repair or replace the leaking exhaust parts as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 11
11. CHECKING FUEL PRESSURE
WARNING:
The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in possible serious or fatal injury.
1. Turn the ignition off.
2. Install Fuel Pressure Decay Tester (8978A) to the fuel rail.
3. Ignition on, engine not running.
4. With the scan tool, actuate the Fuel System test and observe the fuel pressure gauge.
NOTE: Fuel pressure specification: 400 kPa +/- 14 kPa (58 psi +/- 2 psi).
5. Turn the ignition off.
Choose a conclusion that best matches your fuel pressure reading.
Within Specification
- Go To 12
Above Specification
- Replace the fuel filter/pressure regulator. Fuel Pump Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
Below Specification
- Go To 16
12. MAP SENSOR OPERATION
1. Turn the ignition off.
2. Connect a Vacuum Gauge to a Manifold Vacuum source.
3. Start the engine.
4. Allow the engine to idle.
NOTE: If engine will not idle, maintain a constant RPM above idle.
5. Using the scan tool, read the MAP Sensor vacuum value.
Is the scan tool reading within 1" of Hg on the Vacuum Gauge reading?
Yes
- Go To 13
No
- Verify that there is good pin to terminal contact in the MAP Sensor and Powertrain Control Module connectors. If OK, replace the MAP Sensor. .
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
13. ENGINE MECHANICAL PROBLEM
1. Turn the ignition off.
2. Check for any of the following conditions/mechanical problems:
- AIR INDUCTION SYSTEM - must be free from leaks.
- ENGINE VACUUM - must be at least 13 inches in neutral
- ENGINE VALVE TIMING - must be within specifications
- ENGINE COMPRESSION - must be within specifications
- ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks.
- ENGINE PCV SYSTEM - must flow freely
- TORQUE CONVERTER STALL SPEED - must be within specifications
- POWER BRAKE BOOSTER - no internal vacuum leaks
- FUEL - must be free of contamination
- FUEL INJECTOR - plugged or restricted injector; control wire not connected to correct injector
Are there any engine mechanical problems?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 14
14. O2 SENSOR
1. Turn the ignition off.
2. Replace the O2 Sensor and reconnect the harness connector.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Start the engine and allow it to idle long enough for the O2 Sensor to enter closed loop operation.
6. With the scan tool, view DTCs.
Did the DTC return?
Yes
- Go To 15
No
- Repair is complete.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
15. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the related Sensors and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related Sensor and Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module. .
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
16. RESTRICTED FUEL SUPPLY LINE
WARNING:
The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in possible serious or fatal injury.
1. Turn the ignition off.
2. Raise vehicle on hoist and disconnect the fuel pressure line at the fuel pump module.
3. Install Fuel Pressure Decay Tester (8978A) between the fuel supply line and the fuel pump module.
4. Ignition on, engine not running.
5. With the scan tool, actuate the ASD Fuel System test and observe the fuel pressure gauge.
NOTE: Fuel pressure specification: 400 kPa +/- 14 kPa (58 psi +/- 2 psi).
Is the fuel pressure within specification?
Yes
- Repair or replace fuel supply line as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 17
17. FUEL PUMP INLET STRAINER
WARNING:
The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released.
1. Turn the ignition off.
2. Remove the Fuel Pump Module and inspect the Fuel Inlet Strainer.
Is the Fuel Inlet Strainer plugged?
Yes
- Replace the Fuel Pump Inlet Strainer. Fuel Pump Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 18
18. FUEL PUMP MODULE
Repair
- Verify that there is good pin to terminal contact in the Fuel Pump Module, Relay and Powertrain Control Module connectors. If OK, replace the Fuel Pump Module. Fuel Pump Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.