FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P2445






P2445-AIR PUMP SWITCH VALVE STUCK OFF







Theory of Operation

For 20 seconds following a vehicle cold start, the air injection system delivers a controlled amount of outside air into the exhaust system, upstream of the catalytic converters, in order to help reduce hydrocarbon and carbon monoxide gas emissions.

- When Monitored:
After the diagnostics for Airflow Sensor Rationality (P2431) has passed, while the Secondary Air Pump Relay control is active. ECT above 0 C (32 F), ambient air temperature within approximately 2 degrees of ECT, and Secondary Airflow diagnostic counter above 100 (approximately 3.0 seconds).

- Set Condition:
During monitoring, the measured secondary airflow threshold is greater than a calibrated value (approximately 6 kg/h) and the difference between minimum and maximum airflow is greater than a calibrated value (approximately 3.5 kg/h).





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. DTC IS ACTIVE

WARNING: The normal operating temperature of the exhaust system is very high. Never work around or attempt to service any part of the exhaust system until it has cooled. Special care should be taken when working near any part of the exhaust system. The temperature rises to a high level after a short period of engine operating time.

NOTE: Diagnose and repair any Secondary Air system sensor signal or relay control circuit DTCs before proceeding with this procedure.

1. Turn the ignition on.
2. With the scan tool, select View DTCs and review the DTC environmental data for this DTC.

Is the good trip counter greater than 0?

Yes

- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. Checking for an Intermittent DTC.

No

- Go To 2

2. AIR INJECTION SYSTEM COMPONENT INSPECTION

WARNING: The normal operating temperature of the exhaust system is very high. Never work around or attempt to service any part of the exhaust system until it has cooled. Special care should be taken when working near any part of the exhaust system. The temperature rises to a high level after a short period of engine operating time.

1. Turn the ignition off.
2. Inspect the Secondary Air Pump Airflow Sensor, the Secondary Air Pump Assembly, the Secondary Air Pump Valve and the connection tubes between them.
3. Look for damage, obstructions, leaks, or any condition that would obstruct or interfere with airflow between the components.
4. Using the wiring diagram/schematic as a guide, inspect the wiring and electrical connectors at the Secondary Air Pump Airflow Sensor, Secondary Air Pump Relay, and the Secondary Air Pump Assembly.
5. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 3

3. SECONDARY AIR PUMP ACTUATION
1. Turn the ignition on.
2. With the scan tool, actuate the Secondary Air Pump Relay control to on.
3. With the scan tool, monitor the Secondary Air MAF Sensor value.

CAUTION: Do not allow the Air Pump actuation to run for more than 30 seconds at a time. Pump damage may occur. Allow the pump to cool down for at least 10 minutes between actuations.

Is the Secondary Air MAF Sensor value greater than 25 kg/h with the pump actuated on?

Yes

- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. Checking for an Intermittent DTC.

No

- Go To 4

4. SECONDARY AIR CHECK VALVE





WARNING: The normal operating temperature of the exhaust system is very high. Never work around or attempt to service any part of the exhaust system until it has cooled. Special care should be taken when working near any part of the exhaust system. The temperature rises to a high level after a short period of engine operating time.

1. Turn the ignition off.
2. Disconnect the air pump outlet tube (3) from the secondary air check valve (1).
3. Turn the ignition on.
4. With the scan tool, actuate the Secondary Air Pump Relay control to on.
5. With the scan tool, monitor the Secondary Air MAF Sensor value.

CAUTION: Do not allow the Air Pump actuation to run for more than 30 seconds at a time. Pump damage may occur. Allow the pump to cool down for at least 10 minutes between actuations.

Is the Secondary Air MAF Sensor value greater than 25 kg/h with the pump actuated on?

Yes

- Replace the Secondary Air Check Valve.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 5

5. (Z931) GROUND CIRCUIT OPEN OR HIGH RESISTANCE




1. Turn the ignition off.
2. Disconnect the Secondary Air Pump connector.
3. Using a 12-volt test light connected to 12 volts, check the (Z931) Ground circuit in the Secondary Air Pump harness connector.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go To 6

No

- Repair the (Z931) Ground circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

6. SECONDARY AIR PUMP CONTROL OUTPUT




1. Turn the ignition on.
2. With the scan tool, actuate the Secondary Air Pump Relay control to on.
3. Using a 12-volt test light connected to ground, check the (A161) Secondary Air Pump Relay Output circuit in the Secondary Air Pump harness connector.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go To 7

No

- Go To 16

7. (F343) FUSED MAIN RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE




1. Turn the ignition off.
2. Disconnect the Airflow Sensor connector.
3. Turn the ignition on.
4. Using a 12-volt test light connected to ground, check the (F343) Fused Main Relay Output circuit in the Airflow Sensor harness connector.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go To 8

No

- Repair the (F343) Fused Main Relay Output circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

8. (K157) SAF SIGNAL CIRCUIT VOLTAGE




1. Turn the ignition on.
2. Measure the voltage of the (K157) SAF Signal circuit in the Airflow Sensor harness connector.

Is the voltage between 4.8 and 5.01 volts?

Yes

- Go To 9

No

- Go To 12

9. (K957) SENSOR GROUND CIRCUIT TEST




1. Turn the ignition off.
2. Using a 12-volt test light connected to 12 volts, check the (K957) Sensor Ground circuit in the Airflow Sensor harness connector.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go To 10

No

- Go To 14

10. AIRFLOW SENSOR WIRING AND CONNECTORS
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Airflow Sensor and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 11

11. AIRFLOW SENSOR
1. Turn the ignition off.
2. Replace the Airflow Sensor.
3. Verify that all Secondary Air Pump Assembly wiring, connectors, tubes, and hoses are connected properly.
4. Turn the ignition on.
5. With the scan tool, actuate the Secondary Air Pump Relay control to on.
6. With the scan tool, monitor the Secondary Air MAF Sensor value.

CAUTION: Do not allow the Air Pump actuation to run for more than 30 seconds at a time. Pump damage may occur. Allow the pump to cool down for at least 10 minutes between actuations.

Is the Secondary Air MAF Sensor value greater than 25 kg/h with the pump actuated on?

Yes

- Test Complete.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 19

12. (K157) SAF SIGNAL CIRCUIT SHORTED TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the Powertrain Control Module (PCM) harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (K157) SAF Signal circuit in the Airflow Sensor harness connector.

Is there any voltage present?

Yes

- Repair the (K157) SAF Signal circuit for a short to voltage.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 13

13. (K157) SAF SIGNAL CIRCUIT SHORTED TO GROUND




1. Turn the ignition off.
2. Measure the resistance between ground and the (K157) SAF Signal circuit in the Airflow Sensor harness connector.

Is the resistance above 100 Ohms?

Yes

- Go To 14

No

- Repair the (K157) SAF Signal circuit for a short to ground.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

14. (K157) SAF SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE





NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.

1. Measure the resistance of the (K157) SAF Signal circuit between the Airflow Sensor harness connector and the PCM.

Is the resistance below 5.0 Ohms?

Yes

- Go To 20

No

- Repair the (K157) SAF Signal circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

15. (K957) SENSOR GROUND CIRCUIT OPEN OR HIGH RESISTANCE





NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.

1. Measure the resistance of the (K957) Sensor Ground circuit between the Airflow Sensor harness connector and the PCM.

Is the resistance below 5.0 Ohms?

Yes

- Go To 20

No

- Repair the (K957) Sensor Ground for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

16. (A161) SECONDARY AIR PUMP CONTROL OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE




1. Turn the ignition off.
2. Remove the Secondary Air Pump Relay.
3. Measure the resistance of the (A161) Secondary Air Pump Relay Output circuit between the Secondary Air Pump Relay connector and the Secondary Air Pump harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 17

No

- Repair the (A161) Secondary Air Pump Relay Output circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

17. (A929) FUSED B+ CIRCUIT OPEN OR HIGH RESISTANCE




1. Turn the ignition on.
2. Using a 12-volt test light connected to ground, check the (A929) Fused B+ circuit in the Secondary Air Pump Relay connector.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Replace the Secondary Air Pump Relay.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Repair the (A929) Fused B+ circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

18. SECONDARY AIR PUMP RELAY
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Secondary Air Pump Relay and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Replace the Secondary Air Pump Relay.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

19. SECONDARY AIR PUMP
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Secondary Air Pump and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Replace the Secondary Air Pump.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

20. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Secondary Air Pump Assembly and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Replace the Powertrain Control Module (PCM).
- Perform the PCM VERIFICATION TEST. PCM Verification Test.