• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category |
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
HO2S High Signal | P0131, P0132, P0137, P0140, P0151, P0152, P0157, P0158, P1133, , P2A04 | P0131, P0132, P0133, P0134, P0137, P0140, P0151, P0152, P0153, P0154, P0157, P0160, P1133, P1153, | P0131, P0132, P0133, P0134, P0137, P0140, P0151, P0152, P0153, P0154, P0157, P0160, P1133, P1153, | P0132, P0134, P0138, P0140, P0152, P0154, P0158, P0160, P1133, P1153, | P0133, P0134, P0140, P0153, P0154, P0160, P1133, P1153, |
HO2S Low Signal | P2A00, P2A01, P2A03, P2A04 | P0131, P0132, P0133, P0134, P0138, P0140, P0151, P0152, P0153, P0154, P0158, P0160, P1133, P1153, | P0131, P0132, P0133, P0134, P0138, P0140, P0151, P0152, P0153, P0154, P0158, P0160, P1133, P1153, | P0134, P0138, P0140, P0154, P0158, P0160, P1133, P1153, , |
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
---|---|---|---|---|
HO2S High Signal | 200-800 mV | 0 mV | Approximately 470 mV | Approximately 1,100 mV |
HO2S Low Signal | 200-800 mV | 455 mV | Approximately 450 mV | Approximately 445 mV |
Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. Heating elements inside the HO2S minimize the time required for the sensors to reach operating temperature. The engine control module (ECM) supplies the HO2S with a reference or bias, voltage of about 450 mV. When the engine is first started the ECM operates in open loop ignoring the HO2S voltage signal. Once the HO2S reaches operating temperature and Closed Loop is achieved the HO2S generates a voltage within a range of 0-1,000 mV that fluctuates above and below bias voltage. High HO2S voltage indicates a rich exhaust stream; low HO2S voltage indicates a lean exhaust stream.
The HO2S are used for catalyst monitoring. During this test the ECM will force the air-to-fuel ratio rich and/or lean. The ECM then waits for a predicted response from the sensor. If the sensor voltage transitions below 200 mV and/or above 730 mV, the DTC will pass for this ignition cycle.
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0443, P1516, P2101, P2119, P2135 or P2176 are not set. |
• | The Loop Status parameter is Closed. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The Throttle Position (TP) Indicated Angle parameter is between 3-70 percent. |
• | DTC P0131 runs continuously when the above conditions are met for 3 seconds. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P1516, P2101, P2119, P2135 or P2176 are not set. |
• | The Loop Status parameter is Closed. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The Throttle Position (TP) Sensor parameter is between 3-70 percent. |
• | DTC P0132 runs continuously when the above conditions are met for 2 seconds. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P1516, P2101, P2119, P2135 or P2176 are not set. |
• | The Loop Status parameter is Closed. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The TP Sensor parameter is between 3-70 percent. |
• | DTC P0137 runs the lean test continuously when the above conditions are met for 3 seconds. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P1516, P2101, P2119, P2135 or P2176 are not set. |
• | The Loop Status parameter is Closed. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The TP Sensor parameter is between 3-70 percent. |
• | DTC P0138 runs the rich test continuously when the above conditions are met for 3 seconds. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P1516, P2101, P2119, P2135 or P2176 are not set. |
• | The Engine Run Time parameter is more than 100 seconds. |
• | The Engine Speed parameter is between 1,000-3,400 RPM. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The mass air flow (MAF) sensor parameter is between 10-30 g/s. |
• | The ECT sensor parameter is more than 70°C (158°F). |
• | DTC P2A00 runs continuously when the above conditions are met for 5 seconds. |
• | DTCs P0030, P0036, P0053, P0054, P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1133, P1516, P2101, P2119, P2135, P2176, P2A00 are not set. |
• | The Engine Run Time parameter is more than 9.6 minutes. |
• | The ignition 1 Signal parameter is between 10-18 volts. |
• | The MAF sensor parameter is between 3-50 g/s. |
• | The Engine Speed parameter is between 500-5,000 RPM. |
• | The Vehicle Speed parameter is between 55-132 km/h (34-82 mph). |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The Short Term FT parameter is between -4 and +6 percent. |
• | DTC P2A01 runs the intrusive test once per drive cycle when the above conditions are met for 5 second. |
• | The ECM detects that the sensor Voltage parameter is less than 80 mV. |
• | DTC P0131 sets within 50 seconds during the lean test when the above condition is met. |
• | The ECM detects that the sensor parameter is more than 1,050 mV. |
• | DTC P0132 sets within 50 seconds during the rich test when the above condition is met. |
• | The ECM detects that the sensor voltage parameter is less than 80 mV. |
• | DTC P0137 sets within 100 seconds during the lean test when the above condition is met. |
• | The ECM detects that the sensor voltage parameter is more than 950 mV. |
• | DTC P0138 sets within 100 seconds during the rich test when the above condition is met. |
DTCs P0131, P0132, P0137, P0138, P0151, P0152, P0157, P0158, P2A01 or P2A04 are type B DTCs.
DTCs P0131, P0132, P0137, P0138, P0151, P0152, P0157, P0158, P2A01 or P2A04 are type B DTCs.
• | Allow the engine to reach operating temperature. Engine running, using a scan tool observe the affected HO2S parameter. |
- | The HO2S 1 value should vary from below 200 mV to above 800 mV and respond to fuelling changes. |
- | The HO2S 2 value should change more than 200 mV when the throttle is quickly cycled 3 times from Closed to wide open and back to Closed after running the engine at 1,500 RPM for 30 seconds. |
• | If any HO2S heater DTCs are set, diagnose those DTCs first. |
• | The affected HO2S may be damaged due to contamination. Prior to replacing the affected HO2S, inspect for the following sources of contamination: |
Notice: Refer to Silicon Contamination of Heated Oxygen Sensors Notice in the Preface section.
- | A silicon contaminated HO2S |
- | Engine oil consumption--Refer to Oil Consumption Diagnosis. |
- | Engine coolant consumption--Refer to Loss of Coolant . |
⇒ | If more than approximately 40 mV, test the affected HO2S low signal circuit for a short to voltage. If the circuit tests normal, ECM. |
⇒ | If less than approximately 2 mV, test the affected HO2S low signal circuit for open/high resistance. If the circuit tests normal, replace the ECM. |
⇒ | If more than approximately 300 mV, test the affected HO2S high signal circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
⇒ | If less than approximately 300 mV, test the affected HO2S high signal circuit for high resistance. If the circuit tests normal, replace the ECM. |
⇒ | If not 0 mV and all circuits and connectors test normal, replace the ECM. |
⇒ | If not 1,095 mV and all circuits and connectors test normal, replace the ECM. |
Notice: Refer to Diagnostic System Check - Vehicle in the Preface section.
Important:
• Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure. • For DTC P0131 and P0132, in order to make sure that the performance
of the catalyst has not been affected by the fault that set this DTC, operate the
vehicle within the conditions for running and setting DTC P0420 and verify
that P0420 runs and passes. Refer to
DTC P0420 or P0430.
• | Engine Control Module Replacement for engine control module replacement, setup and programming. |