GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2005 🢒 Vibe - FWD 🢒 Restraints 🢒 SIR 🢒 DTC P2445

System Description

The DTC P2445 Secondary Air Injection (AIR) System Pump Stuck Off diagnostic monitors the AIR pump activity. The AIR system helps reduce exhaust emissions. The system forces fresh filtered air into the exhaust stream in order to accelerate the catalyst operation. An electric air pump, the AIR pump, provides filtered air on demand to the AIR shut-off valve. The AIR shut-off valve controls the flow of air from the AIR pump to the exhaust manifold. The AIR solenoid valve supplies the manifold vacuum that is used to operate the AIR shut-off valve. A pressure sensor is used to monitor the air flow from the AIR pump. By comparing the measured pressure against the expected pressure the pressure sensor can detect faults in the AIR pump, AIR shut-off valve, and the AIR solenoid valve. The pressure sensor can also detect leaks in the AIR system plumbing.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P2445 Secondary Air Injection (AIR) System Pump Stuck Off

Conditions for Running the DTC
    • DTCs P0010, P0011, P0012, P0016, P0031, P0032, P0100, P0101, P0102, P0103, P0110, P0112, P0113, P0115, P0117, P0118, P0120, P0121, P0122, P0123, P0125, P0130, P0133, P0134, P0171, P0172, P0300, P0301-P0304, P0325, P0327, P0328, P0335, P0340, P0341, P0351-P0354, P0385, P0450, P0451, P0452, P0453, P2195, P2196, P2430, P2431, P2432, P2433, P2645, P2646, P2647 are not set.
    • The engine is running.
    • DTC P2445 runs continuously once the above condition has been met.

Conditions for Setting the DTC

The pressure sensor indicates that no air flow was detected when the AIR pump was commanded ON.

Action Taken When the DTC Sets
    • The powertrain control module (PCM) illuminates the malfunction indicator lamp (MIL) during the second key cycle in which the DTC sets.
    • The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Freeze Frame buffer.

Conditions for Clearing the MIL/DTC
    • The PCM turns OFF the MIL on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present.
    • A DTC will clear after 40 consecutive warm-up cycles have occurred without a fault.
    • A DTC can be cleared by using the scan tool Clear Information function.

Diagnostic Aids

Inspect for any of the following conditions:

    • The resistance of the AIR pump relay--The resistance across terminal 1 and terminal 2 is 85-95 ohms at 20°C (68°F). The resistance across terminal 3 and terminal 4 is infinite.
    • The AIR pump relays electrical contacts may be pitted or sticking. Replace the relay if tapping gently on the relay or wiggling the relay causes a change in the relays operation.
    • The performance of the AIR pump relay may be affected by temperature. Check the relay after sitting outside overnight and after running the engine 30 minutes.
    • An intermittent malfunction may be caused by a fault in an AIR system electrical circuit. Inspect the wiring harness and components for an intermittent condition. Refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

    2.

  2. This step checks for the operation of the AIR pump.

    3.

  3. This step checks for a pulled low solenoid control circuit. If the AIR solenoid is always ON, the pressure sensor will not detect any air flow.

    4.

  4. This step checks for an always open AIR solenoid valve. If the AIR solenoid is always ON, the pressure sensor will not detect any air flow.

    5.

  5. This step checks the control circuit of the AIR pump relay.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn ON the ignition, with the engine OFF.
  2. Command the secondary air injection (AIR) solenoid and AIR pump ON with the scan tool. Refer to Scan Tool Output Controls .

Did the AIR pump operate for approximately 5 seconds when commanded ON?

Go to Step 3

Go to Step 6

3

Inspect the AIR system hoses, pipes, and fittings for a leak between the AIR pump and the AIR shut-off valve.

Do you find and repair a leak?

Go to Step 19

Go to Step 4

4

  1. Disconnect the electrical connector of the AIR solenoid valve.
  2. Use a test lamp to jumper between the solenoid ignition positive volage circuit and the solenoid control circuit.
  3. Turn ON the ignition, with the engine OFF.

Did the test lamp illuminate?

Go to Step 14

Go to Step 5

5

  1. Disconnect the 2 vacuum hoses from the AIR solenoid valve.
  2. Connect a hand vacuum pump to one of the solenoid vacuum ports.
  3. Apply 10 inches of vacuum with the hand vacuum pump.

Did the solenoid hold vacuum?

Go to Diagnostic Aids

Go to Step 15

6
  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 cavity 4 and cavity 2 with a test lamp connected to ground.

Did the test lamp illuminate at both cavities?

Go to Step 7

Go to Step 9

7

  1. Probe the AIR pump relay control circuit cavity 1 with a test lamp connected to B+.
  2. Command the AIR pump ON with the scan tool.

Did the test lamp illuminate?

Go to Step 10

Go to Step 8

8
  1. Check for an open in the AIR pump relay control circuit.
  2. Repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a wiring fault found and repaired?

Go to Step 19

Go to Step 18

9
  1. Check for the cause of no ignition positive voltage to the AIR pump relay.
  2. Repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 19

--

10
  1. Disconnect the AIR pump electrical connector.
  2. Probe the switched ignition positive voltage circuit of the AIR pump, at harness connector terminal 2, with a test lamp connected to ground.
  3. Command the AIR pump ON with the scan tool.

Did the test lamp illuminate?

Go to Step 11

Go to Step 13

11

Connect the test lamp between the AIR pump ground circuit and B+.

Does the test lamp illuminate?

Go to Step 17

Go to Step 12

12

Repair the open in the switched positive voltage circuit of the AIR pump ground. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 19

--

13
  1. Inspect for an open in the switched ignition positive voltage circuit of the AIR pump between the AIR pump relay and the AIR pump.
  2. Repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a wiring fault found and repaired?

Go to Step 19

Go to Step 16

14
  1. Inspect the for a short to ground in the solenoid control circuit.
  2. Repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 19

Go to Step 18

15

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

Did you complete the replacement?

Go to Step 19

--

16

Replace the AIR pump relay.

Did you complete the replacement?

Go to Step 19

--

17

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

Did you complete the replacement?

Go to Step 19

--

18

Replace the powertrain control module (PCM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 19

--

19
  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC.

Did a DTC P2445 set?

Go to Step 2

Go to Step 20

20

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 - Vehicle in Vehicle DTC Information

System OK