Description
The control module activates the secondary air injection (AIR) system by grounding both the pump relay and the vacuum control solenoid control circuits simultaneously. This energizes the AIR pump and the vacuum control solenoid. Vacuum is then applied, opening the valves. The pump then forces fresh air into the exhaust stream in order to accelerate catalyst operation. The control module will run up to 3 diagnostic tests using the pre-catalyst heated oxygen sensor (HO2S) voltage and the Short Term FT in order to diagnose the system. The system can be diagnosed during normal Secondary Air Injection operation or the control module can activate the system specifically for diagnostic purposes. If an air flow problem is detected this diagnostic trouble code (DTC) will set. When inactive, the system prevents air flow in either direction.
Conditions for Running the DTC
| • | DTCs P0102, P0103, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0125, P0128, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0171, P0172, P0300, P0440, P0442, P0443, P0446, P0449, P0506, P0507, P1111, P11112, P1114, P1115, P1121, P1122, P1133, or P1134 are not set. |
| • | The engine run time is more than 10 seconds. |
| • | The ECT is between 4.5°C and 110°C (40°F - 230°F). |
| • | The MAF is between 2 to 25 g/s. |
| • | The ignition voltage is more than 10 volts. |
| • | The engine speed is more than 800 RPM. |
| • | The fuel system is operating in DECEL control cell. |
| • | The IAT is between 4.5°C and 70°C (40°F - 158°F). |
| • | The short term fuel trim is between .97 and 1.03. |
| • | The engine load is between 5 and 30 percent. |
| • | BARO is above 75 kPa (10.8 psi). |
| • | The vehicle speed is more than 40 km/h (25 mph). |
Conditions for Setting the DTC
| • | The pre-catalyst HO2S voltage remains above a predetermined lean value during the test. |
| AND |
| • | The Short Term FT does not increase a calibrated amount during the test. |
| • | Both conditions above exist for 3 consecutive 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
If the problem is intermittent, refer to Symptoms - Engine Controls .
If the DTC cannot be duplicated and is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set. Also refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
A short to voltage in the pump relay control circuit can result in the AIR pump running continuously with the ignition OFF by backfeeding to ground. This will eventually result in pump failure.
An AIR pump that had become inoperative and had shown indications of having exhaust gases in the outlet port would indicate check valve failure.
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |||||||
2 |
Important: If DTC P0412 or DTC P0418 are also set, refer to that diagnostic first. Inspect the for the following conditions:
Did you find and correct the condition? | Go to Step 42 | Go to Step 3 | ||||||
3 |
Does the pump turn ON and OFF with each command? | Go to Step 4 | Go to Step 10 | ||||||
4 | With a scan tool, command the AIR solenoid ON and OFF. Does the solenoid turn ON and OFF with each command? | Go to Step 5 | Go to Step 14 | ||||||
5 |
Is airflow present at the hose outlet? | Go to Step 6 | Go to Step 16 | ||||||
6 |
Is vacuum present at the vacuum line? | Go to Step 7 | Go to Step 4 | ||||||
7 |
Is vacuum present at the vacuum line? | Go to Step 8 | Go to Step 17 | ||||||
8 |
Does the valve hold vacuum for 1 minute? | Go to Step 9 | Go to Step 33 | ||||||
9 |
Important: Attempt to blow through the valve without vacuum applied. If you can blow through the valve, refer to step 33.
Can you blow through the valve? | Go to Step 25 | Go to Step 33 | ||||||
10 | Does the pump run continuously? | Go to Step 18 | Go to Step 1 | ||||||
11 |
Does the test lamp illuminate when probing both circuits? | Go to Step 12 | Go to Step 20 | ||||||
12 |
Does the test lamp turn ON and OFF with each command? | Go to Step 13 | Go to Step 23 | ||||||
13 |
Does the AIR pump operate? | Go to Step 34 | Go to Step 26 | ||||||
14 |
Does the test lamp illuminate? | Go to Step 15 | Go to Step 20 | ||||||
15 |
Does the test lamp turn ON and OFF with each command? | Go to Step 36 | Go to Step 23 | ||||||
16 |
Is airflow present at the pump outlet? | Go to Step 25 | Go to Step 39 | ||||||
17 | Inspect the vacuum line from the solenoid to the valve for a restriction or a loose condition. Did you find and correct the condition? | Go to Step 42 | Go to Step 37 | ||||||
18 |
Does the pump stop operating? | Go to Step 19 | Go to Step 28 | ||||||
19 |
Does the test lamp turn ON and OFF with each command? | Go to Step 35 | Go to Step 29 | ||||||
20 | Inspect the feed fuse or fuses. Is the fuse or fuses OK? | Go to Step 30 | Go to Step 21 | ||||||
21 | Test the feed circuit corresponding to the blown fuse or fuses for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 42 | Go to Step 22 | ||||||
22 | Test the pump feed for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 42 | Go to Step 39 | ||||||
23 | Is the test lamp on steady? | Go to Step 29 | Go to Step 32 | ||||||
24 | Repair the vacuum source. Did you complete the repair? | Go to Step 42 | -- | ||||||
25 | Repair the pipe, hose or check valve for an open or a restriction. Did you find and correct the condition? | Go to Step 42 | Go to Restricted Exhaust in Engine Exhaust | ||||||
26 |
Does the test lamp illuminate? | Go to Step 38 | Go to Step 27 | ||||||
27 |
Does the test lamp illuminate? | Go to Step 31 | Go to Step 30 | ||||||
28 | Repair the short to voltage in the pump feed circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 42 | -- | ||||||
29 | Test for a short to ground in the control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 42 | Go to Step 41 | ||||||
30 | Repair the open pump feed circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 42 | -- | ||||||
31 | Repair the open ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 42 | -- | ||||||
32 |
Important: If diagnosis reveals a short to voltage in the AIR pump relay control circuit, be sure to check AIR pumps. Refer to Diagnostic Aids. Test for an open or short to voltage in the control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 42 | Go to Step 40 | ||||||
33 | Replace the valve. Refer to Secondary Air Injection Shut-Off Valve Outlet Pipe/Hose Replacement . Did you complete the repair? | Go to Step 42 | -- | ||||||
34 | Test for poor connections at the relay. 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 42 | Go to Step 35 | ||||||
35 | Replace the relay. Did you complete the repair? | Go to Step 42 | -- | ||||||
36 | Test for poor connections at the solenoid. 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 42 | Go to Step 37 | ||||||
37 | Replace the solenoid. Refer to Secondary Air Injection Vacuum Control Solenoid Valve Replacement . Did you complete the repair? | Go to Step 42 | -- | ||||||
38 | Test for poor connections at the pump. 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 42 | Go to Step 39 | ||||||
39 |
Important: After you have replaced the pump, turn ON the ignition, with the engine OFF. If the pump runs without a scan tool command, refer to step 18. Replace the pump. Refer to Secondary Air Injection Pump Replacement . Did you complete the repair? | Go to Step 42 | -- | ||||||
40 | Test for poor connections at the control module. 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 42 | Go to Step 41 | ||||||
Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the repair? | Go to Step 42 | -- | |||||||
42 |
Does the DTC reset? | Go to Step 2 | System OK | ||||||
