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.
This diagnostic procedure supports the following DTC:
DTC P2445 Secondary Air Injection (AIR) System Pump Stuck Off
• | 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. |
The pressure sensor indicates that no air flow was detected when the AIR pump was commanded ON.
• | 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. |
• | 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. |
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 . |
The numbers below refer to the step numbers on the diagnostic table.
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.
This step checks for the operation of the AIR pump.
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.
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.
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 | |||
Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | |
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 |
Did the test lamp illuminate? | Go to Step 14 | Go to Step 5 | |
Did the solenoid hold vacuum? | Go to Diagnostic Aids | Go to Step 15 | |
6 |
Did the test lamp illuminate at both cavities? | Go to Step 7 | Go to Step 9 |
Did the test lamp illuminate? | Go to Step 10 | Go to Step 8 | |
8 |
Was a wiring fault found and repaired? | Go to Step 19 | Go to Step 18 |
9 |
Did you complete the repair? | Go to Step 19 | -- |
10 |
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 |
Was a wiring fault found and repaired? | Go to Step 19 | Go to Step 16 |
14 |
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 |
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 |