Circuit Description
The powertrain control module (PCM) activates the secondary air injection (AIR) system by grounding the AIR relay. This energizes the pump and the vacuum control solenoid. As vacuum is applied to the shut-off valve, fresh air is allowed to pass through the pump and vacuum control solenoid. The AIR pump forces fresh air past the shut-off valve and into the exhaust stream in order to accelerate catalyst operation. The PCM will run up to 3 diagnostic tests using the O2S 1 voltage and short term FT to verify system operation. The system can be diagnosed during normal AIR operation or the scan tool can activate the system specifically for diagnostic purposes. If an airflow problem is detected this, DTC will set. When inactive, the shut-off valve prevents air flow in either direction.
Conditions for Running the DTC
| • | DTCs P0105, P0107, P0108, P0112, P0113, P0122, P0123, P0130, P0131, P0132, P0133, P0134, P0171, P0172, P0177, P0178, P0179, P0182, P0183, P0300, P0301-P0304, P0341, P0506, P0507, P0601, P0602, or P1681 are not set. |
| • | The AIR system is commanded ON for more than 20 seconds. |
| • | The intake air temperature (IAT) is between 1-151°C (32-302°F). |
| • | The engine coolant temperature (ECT) is between 5-114°C (41-230°F). |
| • | The battery voltage is more than 11.7 volts. |
| • | The engine run time is more than 200 seconds. |
| • | The calculated airflow is more than 11 g/s. |
| • | The accumulated flow is between 240-600 counts. |
| • | A fuel trim cell of 16 or 17. |
| • | The throttle position (TP) sensor changes less than 5 percent. |
| • | A stabilization time of more than 1 second. |
| • | The fuel ethanol composition is less than 15 percent. |
| • | The manifold absolute pressure (MAP) sensor is less than 30 kPa. |
| • | The fuel injector base pulse width is more 1.35 ms. |
| • | The engine speed is more than 1,150 RPM for auto transmissions. |
| • | The engine speed is more than 1,000 RPM for manual transmissions. |
Conditions for Setting the DTC
The control module detects that the O2S is less than 50 mV for 1 second during a 3-second active test, for 3 consecutive 3-second active tests.
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
An intermittent may be caused by any of the following conditions:
| • | Low system airflow may cause this DTC to set. |
| • | Excessive exhaust system back pressure |
| • | Moisture, water, or debris ingested into the AIR pump |
| • | Pinched, kinked, heat damaged, or deteriorated hoses or vacuum lines |
| • | Restrictions in the pump, inlet duct, or filter |
| • | An AIR pump that has become inoperative and showing signs of exhaust gases in the outlet port would indicate a check valve failure. |
Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step checks for a restriction in the engine vacuum supply to the AIR shut-off valve.
-
This step determines if the lack of air is caused by an open in the AIR supply hose or a defective shut-off valve.
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||
2 | Turn ON the ignition, with the engine OFF. Does the secondary air injection (AIR) pump run constantly? | -- | Go to Step 3 | Go to Step 4 | ||||||
3 |
Does the AIR pump run constantly? | -- | Go to Step 11 | Go to Step 5 | ||||||
4 | Command the AIR pump ON and OFF with a scan tool. Does the AIR pump turn ON and OFF? | -- | Go to Step 13 | Go to Step 6 | ||||||
5 |
Does the test lamp illuminate? | -- | Go to Step 46 | Go to Step 54 | ||||||
6 |
Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 29 | ||||||
7 | Probe the ignition 1 voltage circuit of the AIR pump relay with a test lamp connected to a good ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 10 | ||||||
8 |
Does the test lamp turn ON and OFF? | -- | Go to Step 9 | Go to Step 25 | ||||||
9 |
Does the test lamp turn ON and OFF? | -- | Go to Step 12 | Go to Step 30 | ||||||
10 | Is ignition E fuse open? | -- | Go to Step 36 | Go to Step 50 | ||||||
11 |
Does the test lamp illuminate? | -- | Go to Step 48 | Go to Step 28 | ||||||
12 | Probe the AIR pump ground circuit of the AIR pump with a test lamp connected to battery positive. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 42 | Go to Step 49 | ||||||
13 |
Does the Short Term FT increase by the minimum specified amount in the time given? | 12% in 6 seconds | Go to Diagnostic Aids | Go to Step 14 | ||||||
14 |
Does the test lamp illuminate? | -- | Go to Step 15 | Go to Step 49 | ||||||
15 |
Does the test lamp turn ON and OFF? | -- | Go to Step 16 | Go to Step 27 | ||||||
Does the vacuum increase to more than the specified value then drop back to zero inches? | 14 in Hg | Go to Step 17 | Go to Step 19 | |||||||
17 |
Is air pressure present at the AIR crossover hose? | -- | Go to Step 45 | Go to Step 18 | ||||||
Is air pressure present at the outlet of the AIR shut-off valve? | -- | Go to Step 52 | Go to Step 24 | |||||||
19 |
Does vacuum increase to the specified value, then drop back to zero? | 14 in Hg | Go to Step 22 | Go to Step 20 | ||||||
20 |
Is vacuum more than the specified value? | 14 in Hg | Go to Step 41 | Go to Step 21 | ||||||
21 |
Important: Inspect the vacuum check valve for proper installation. The tapered side of the check valve goes towards the vacuum source. Is the vacuum more than the specified value? | 14 in Hg | Go to Step 44 | Go to Step 23 | ||||||
22 | Inspect the vacuum hose between the AIR vacuum control solenoid and the AIR shut-off valve for a restriction or loose condition and repair as necessary. Did you find and correct the condition? | -- | Go to Step 59 | -- | ||||||
23 | Inspect the vacuum hose between the vacuum check valve and the vacuum source port for a restriction or a loose condition. Did you find and correct the condition? | -- | Go to Step 51 | Go to Intake Manifold Cleaning and Inspection in Engine Mechanical | ||||||
24 |
Is air pressure present at the outlet hose? | -- | Go to Step 55 | Go to Step 26 | ||||||
25 | Test the AIR pump relay control circuit for an open or short to voltage between the powertrain control module (PCM) and the relay. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 43 | ||||||
26 |
Does the air pressure flow at the AIR pump outlet? | -- | Go to Step 38 | Go to Step 56 | ||||||
27 |
Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 57 | ||||||
28 | Test the AIR vacuum control solenoid feed circuit for a short to voltage circuit between the AIR vacuum control solenoid fuse and the AIR solenoid. Refer to Wiring Repairs and Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 59 | -- | ||||||
29 | Is the AIR fuse open? | -- | Go to Step 31 | Go to Step 33 | ||||||
30 | Test the AIR pump supply voltage circuit for an open or for high resistance between the AIR pump relay and the AIR pump. Refer to Wiring Repairs and Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 40 | ||||||
31 | Test the battery positive voltage circuit between the AIR fuse and the AIR pump relay for a short to ground. Refer to Wiring Repairs and Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 32 | ||||||
32 | Test the AIR pump supply voltage circuit or a short to ground between the AIR pump relay and the AIR pump. Refer to Wiring Repairs and Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 35 | ||||||
33 | Test the battery positive voltage circuit between the battery fuse and the AIR fuse for an open. Refer to Wiring Repairs and Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 34 | ||||||
34 | Test the battery positive voltage circuit between the AIR fuse and the AIR pump relay for an open. Refer to Wiring Repairs and Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 47 | ||||||
35 |
Does the fuse open? | -- | Go to Step 54 | Go to Step 56 | ||||||
36 |
Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 37 | ||||||
37 |
Does the ignition E fuse open? | -- | Go to Step 39 | Go to Step 54 | ||||||
38 | Inspect for a restriction or a leak in the AIR pump inlet or outlet hoses and repair as necessary. Did you find and correct the condition? | -- | Go to Step 59 | Go to Step 56 | ||||||
39 | Inspect the related components on this circuit. Refer to Power Distribution Schematics . Did you find and correct the condition? | -- | Go to Step 59 | -- | ||||||
40 | Inspect for poor connections at the AIR pump relay electrical connector. 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 59 | Go to Step 54 | ||||||
41 | Inspect for poor connections at the AIR vacuum control solenoid electrical connector. 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 59 | Go to Step 57 | ||||||
42 | Inspect for poor connections at the AIR pump electrical connector. 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 59 | Go to Step 56 | ||||||
43 | Inspect for poor 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 59 | Go to Step 58 | ||||||
44 |
Did you find and correct the condition? | -- | Go to Step 51 | Go to Step 53 | ||||||
45 |
Did you find and correct the condition? | -- | Go to Step 59 | -- | ||||||
46 | Repair the short to ground in the AIR pump relay control circuit. Did you complete the repair? | -- | Go to Step 59 | Go to Step 58 | ||||||
47 | Repair the short to ground between the battery supply and the AIR pump relay. Refer Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 59 | -- | ||||||
48 | Repair the short to voltage in the AIR pump supply voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 59 | -- | ||||||
49 | Repair the open or high resistance in the ground connection or the ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 59 | -- | ||||||
50 | Repair the open in the ignition 1 voltage circuit between the ignition E fuse and the AIR pump relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 59 | -- | ||||||
51 | Replace the vacuum hose. Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
52 | Replace the AIR crossover hose. Refer to Secondary Air Injection Crossover Pipe/Hose Replacement . Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
53 | Replace the vacuum check valve of the AIR pump. Refer to Secondary Air Injection Check Valve Replacement . Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
54 | Replace the AIR pump relay. Refer to Relay Replacement . Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
55 | Replace the AIR shut-off valve. Refer to Secondary Air Injection Shutoff Valve Replacement . Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
56 | Replace the AIR pump. Refer to Secondary Air Injection Pump Replacement . Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
57 | Replace the AIR vacuum control solenoid valve. Refer to Secondary Air Injection Vacuum Control Solenoid Valve Replacement . Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
58 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 59 | -- | ||||||
59 |
Does the DTC run and pass? | -- | Go to Step 60 | Go to Step 2 | ||||||
60 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |||||||
