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For 1990-2009 cars only

Circuit Description

The secondary air injection (AIR) pump used on this vehicle lower tail pipe emissions during start-up. The AIR system consists of the following items:

    • The AIR pump
    • The shut-off valves
    • The vacuum control solenoid valve
    • The system hoses/piping
    • The AIR relay, fuses, and related wiring

The powertrain control module (PCM) uses the AIR relay to control the AIR pump. The PCM also controls the AIR vacuum control solenoid valve that supplies vacuum to the AIR shut-off valves. With the AIR system inactive, the AIR shut-off valves prevent air flow in either direction. With the AIR system active, the PCM applies ground to the AIR relay, and the vacuum control solenoid valve. Fresh air flows from the pump, through the system hoses, past the shut-off valves, and into the exhaust stream. The air helps the catalyst quickly reach normal working temperature, thus lowering the tail pipe emissions on a start-up. The PCM tests the AIR system for the following conditions:

    • AIR system, overall system including both banks, and results in DTC P0410
    • AIR system bank 1 (DTC P1415)
    • AIR system bank 2 (DTC P1416)
    • AIR relay (DTC P0418)
    • AIR vacuum control solenoid (DTC P0412)

The PCM runs two tests to diagnose the AIR system: Passive, and Active. Both tests involve a response from the fuel control heated oxygen sensors (HO2S) bank 1 sensor 1 and HO2S bank 2 sensor 2. If both passive tests pass, the PCM takes no further action. If either part of the passive test fails, or is inconclusive, the PCM initiates the Active tests. If the PCM determines that the HO2S voltages did not respond as expected during the tests, DTC P0410. For further information concerning the AIR system and system tests, refer to Secondary Air Injection System Description .

Conditions for Running the DTC

Passive Tests

    • DTCs P0102, P0103 P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0121, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0151, P0152, P0153, P0154, P0155, P0157, P0158, P0161, P0200, P0300, P0335, P0336, P0351, P0352, P0353, P0354, P0355, P0356, P0357, P0358, P0506, P0507, P1133, P1134, P1138, or P1171 are not set.
    • The engine is running for more than 2 seconds.
    • The engine speed is more than 1000 RPM.
    • The throttle is steady.
    • The engine load is less than 80 percent .
    • The system voltage is more than 10.5 volts.
    • The mass air flow (MAF) is less than 35 g/s.
    • The air fuel ratio is more than 11.1:1
    • The engine coolant temperature (ECT) is between 5-110°C (41-230°F).
    • The intake air temperature (IAT) is between 5-72.5°C (41-162.5°F).
    • The power enrichment, or deceleration fuel cut-off (DFCO) not active.
    • The start up engine coolant temperature (ECT) is between 5-80°C (41-176°F).

Active Tests

    • The engine is running.
    • The engine speed is more than 1000 RPM.
    • The throttle is steady.
    • The engine load is less than 80 percent .
    • The system voltage is more than 10.5 volts.
    • The mass air flow (MAF) is less than 75 g/s.
    • The fuel system is in Closed Loop operation.
    • The evaporative emission (EVAP) purge is active.
    • The engine coolant temperature (ECT) is more than 68°C (154°F).
    • The short term fuel trim is between -3 and +3 percent.
    • The fuel trim is in cells 4, 5, or 6.

Conditions for Setting the DTC

Passive Tests

    • During the operation of the AIR pump, the HO2S voltage for both fuel control sensors is above 300 mV for 12 seconds, 350 mV for 9 seconds on a hot start.
    • When the AIR pump is turned OFF, the HO2S voltage for both fuel control sensors is below 600 mV for 25 seconds, 7 seconds on a hot start.
    • The condition is present for 3 occurrences.

Active Test

The HO2S voltage for both fuel control sensors is above 250 mV for 3 occurrences.

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 air flow may cause this DTC to set.
       - Excessive exhaust system back-pressure
       - Moisture, water, or debris ingestion into the AIR pump.
       - Pinched, kinked, heat damaged, or deteriorated hoses or vacuum lines
       - Restrictions in the pump inlet, duct, or filter
    • If the condition is intermittent, refer to Intermittent Conditions .

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Is the AIR pump fuse OK?

Go to Step 3

Go to Step 14

3

Did DTC P0412 or DTC P0418 also set?

Go to DTC P0412 or DTC P0418

Go to Step 4

4

  1. Install the scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Command the AIR system ON and OFF with a scan tool.

Does the AIR pump turn ON and OFF?

Go to Step 9

Go to Step 5

5

Important:  Refer to Electrical Center Identification Views in Wiring Systems for relay terminal identification.

  1. Turn OFF the ignition.
  2. Remove the AIR pump relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the AIR pump relay B+ supply circuit terminal on the switch side of the relay using the J 35616-200 Test Lamp connected to a good ground. Refer to Using Connector Test Adapters in Wiring Systems.

Does the test lamp illuminate?

Go to Step 6

Go to Step 16

6

Jumper the B+ terminal to the AIR pump feed circuit at the relay harness connector using a fused maxi 40-amp jumper wire.

Does the AIR pump turn ON?

Go to Step 22

Go to Step 7

7

  1. Ensure that the jumper still installed.
  2. Disconnect the AIR pump electrical connector.
  3. Probe the AIR Pump Supply Voltage circuit at the AIR pump electrical connector using the J 35616-200 Test Lamp connected to battery ground. Refer to Using Connector Test Adapters in Wiring Systems.

Does the test lamp illuminate?

Go to Step 8

Go to Step 17

8

Connect the J 35616-200 Test Lamp between the AIR Pump Supply Voltage circuit and the ground circuit of the AIR pump harness connector.

Does the test lamp illuminate?

Go to Step 24

Go to Step 18

9

  1. Disconnect the vacuum source from the AIR solenoid valve. Refer to Secondary Air Injection Vacuum Control Solenoid Valve Replacement .
  2. Connect a vacuum gage to the vacuum source.
  3. Start and idle the engine.

Does the vacuum gage display engine vacuum?

Go to Step 10

Go to Step 21

10

  1. Turn OFF the ignition.
  2. Connect the vacuum source to the AIR solenoid valve.
  3. Disconnect the vacuum hose to the AIR shut-off valves at the AIR solenoid valve.
  4. Connect a vacuum gage to the AIR solenoid valve port.
  5. Start and idle the engine.
  6. Command the AIR system ON with a scan tool.

Does the vacuum gage display engine vacuum?

Go to Step 11

Go to Step 23

11

Inspect the vacuum lines to each AIR shut-off valve for the following conditions:

    • Kinks
    • Restrictions
    • Poor connections
    • Damage
    • Leaks

Did you find and correct the condition?

Go to Step 21

Go to Step 12

12

  1. Disconnect both AIR intermediate hoses/pipes from the AIR shut-off valves.
  2. Start and idle the engine.
  3. Command the AIR system ON with a scan tool.

Is air pressure present at both hoses?

Go to Intermittent Conditions

Go to Step 13

13

  1. Inspect for restrictions, poor connections, or damage at the following locations:
  2. • The AIR inlet hose and AIR outlet hose from the AIR pump
    • The AIR intermediate hoses/pipes
    • The AIR crossover hose/pipe
    • The AIR pump
  3. Repair as necessary. Refer to Secondary Air Injection Pump Outlet Pipe/Hose Replacement , Secondary Air Injection Crossover Pipe/Hose Replacement , Secondary Air Injection Pump Intermediate Pipe/Hose Replacement - Bank 1 , Secondary Air Injection Pump Intermediate Pipe/Hose Replacement - Bank 2 , or Secondary Air Injection Pump Replacement .

Did you find and correct the condition?

Go to Step 26

Go to Intermittent Conditions

14

  1. Turn OFF the ignition.
  2. Remove the AIR pump relay from the underhood electrical center.
  3. Remove the AIR pump fuse from the underhood electrical center.
  4. Probe the battery feed terminal for the AIR pump relay harness connector with the J 35616-200 Test Lamp connected to B+.

Does the test lamp illuminate?

Go to Step 19

Go to Step 15

15

  1. Disconnect the AIR pump harness connector at the pump.
  2. Probe the AIR pump supply voltage circuit at the harness connector with the J 35616-200 Test Lamp connected to battery voltage.

Does the test lamp illuminate?

Go to Step 20

Go to Step 25

16

Repair the open circuit between the fuse and the relay. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

--

17

Repair the open circuit between the AIR pump and the AIR pump relay. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

--

18

Repair the poor ground connection or the open ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

--

19

Repair the short to ground in the ignition feed circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

--

20

Repair the short to ground in the circuit between the AIR pump relay and the AIR pump. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 26

--

21

Replace the vacuum hose or vacuum check valve as necessary.

Did you complete the replacement?

Go to Step 26

--

22

Replace the AIR pump relay.

Did you complete the replacement?

Go to Step 26

--

23

Replace the AIR solenoid valve. Refer to Secondary Air Injection Vacuum Control Solenoid Valve Replacement .

Did you complete the replacement?

Go to Step 26

--

24

  1. Inspect for poor connections at the AIR pump electrical connector. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
  2. Repair the poor connection as necessary. Refer to Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

Go to Step 26

Go to Step 25

25

Replace the AIR pump. Refer to Secondary Air Injection Pump Replacement .

Did you complete the replacement?

Go to Step 26

--

26

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run and pass?

Go to Step 27

Go to Step 2

27

With a scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK