Circuit Description
When the vehicle is first started, the engine operates in an Open Loop operation, ignoring the oxygen sensor (O2S) signal and calculating the air-to-fuel ratio based on inputs from the engine coolant temperature (ECT), the throttle position (TP), and the manifold absolute pressure (MAP) sensors only. The powertrain control module (PCM) will begin by using the heated oxygen sensor (HO2S) signal in order to control the fuel delivery in a Closed Loop when the following conditions are met:
| • | The engine has run a minimum amount of time based on ECT at engine start-up. |
| • | The HO2S 1 has a varying voltage output. This voltage output indicates that the HO2S is hot enough to operate properly. |
| • | The ECT has increased a minimum amount based on the ECT at engine start-up. |
Conditions For Running The DTC
| • | DTCs P0105, P0107, P0108, P0116, P0117, P0118, P0122, P0123, P0125, P0128, P0131, P0132, P0133, P0134, P0171, P0172, P0201-P0204, P0300, P0301-P0304, P0325, P0336, P0440, P0442, P0446, P0452, P0453, P0502, P0601, P0602, P1133, P1441, or P1621 are not set. |
| • | The engine has been running more than 100 seconds. |
| • | The engine speed is between 1,200-3,400 RPM. |
| • | The TP angle is between 10-40 percent. |
| • | The ECT is more than 60°C (140°F). |
| • | The above conditions have been met for 2 seconds. |
Conditions For Setting The DTC
The engine is not in Closed Loop for 5 seconds out of 12.5 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
DTC P0130 or a slow response is most likely caused by one of the following items:
HO2S 1 contamination--Inspect the HO2S 1 for silicone contamination from fuel or the use of improper room-temperature vulcanizing (RTV) sealant. The HO2S 1 sensor may have a white powdery coating, which will result in a high but false voltage signal indicative of rich exhaust . The PCM will then reduce the amount of fuel delivered to the engine, and cause a severe surge or driveability problem.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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When the system is operating correctly, the HO2S voltage should toggle above and below the specified values.
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The specified value measures on a correctly operating system.
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The specified value measures on a correctly operating system.
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||
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Important: If any other DTCs are set except for HO2S DTCs, refer to the other DTCs first before proceeding with this table.
Does the scan tool indicate that the HO2S 1 voltage is more than or less than the specified values? | 400-500 mV | Go to Step 3 | Go to Step 4 | |||||||
3 | Operate the vehicle within the Failure Records conditions. Does the scan tool indicate that this DTC failed this ignition? | -- | Go to Step 4 | Go to Diagnostic Aids | ||||||
4 | Inspect and test for the following:
Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 5 | ||||||
Does the voltage measure within the specified value? | 351-551 mV | Go to Step 6 | Go to Step 8 | |||||||
Does the scan tool indicate HO2S 1 voltage at or near the specified value? | 0 mV | Go to Step 9 | Go to Step 7 | |||||||
7 | Test the low signal circuit for an open, high resistance, or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 | ||||||
8 | Test the high signal circuit for an open, high resistance, or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 | ||||||
9 | Test for faulty connections at the HO2S 1 sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 | ||||||
10 |
Important: Determine the cause of contamination before replacing the sensor. Inspect and test for the following:
Replace the affected HO2S 1 sensor. Refer to Heated Oxygen Sensor Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||
11 | Test for faulty connections at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 | ||||||
12 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||
13 |
Does the DTC run and pass? | -- | Go to Step 14 | Go to Step 2 | ||||||
14 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |||||||
