FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

P2433






P2433-SECONDARY AIR INJECTION SYSTEM AIR FLOW SENSOR CIRCUIT HIGH







- When Monitored:
With the engine running and battery voltage greater than 10 volts.

- Set Condition:
The PCM detects that the sensor input voltage is above the maximum acceptable value.





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.

1. Start the engine and allow it to reach normal operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

NOTE: Diagnose and repair any system voltage or sensor supply voltage DTCs before continuing with this test.

2. With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

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

2. (K157) SAF SIGNAL CIRCUIT VOLTAGE




1. Turn the ignition off.
2. Disconnect the Secondary Air Flow Sensor connector.
3. Turn the ignition on.
4. Measure the voltage of the (K157) SAF Signal circuit in the Secondary Air Flow Sensor harness connector.

Is the voltage between 4.8 and 5.2 volts?

Yes

- Go To 3

No

- Go To 4

3. (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 Secondary Air Flow 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

- Go To 7

4. (K157) SAF SIGNAL CIRCUIT SHORTED TO VOLTAGE




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

5. (K157) SAF SIGNAL CIRCUIT SHORTED TO THE (F343) FUSED ASD/MAIN RELAY OUTPUT CIRCUIT




1. Turn the ignition off.
2. Measure the resistance between the (K157) SAF Signal circuit and the (F343) Fused ASD/Main Relay Output in the Secondary Air Flow Sensor harness connector.

Is the resistance below 100 Ohms?

Yes

- Repair the (K157) SAF Signal circuit for a short to the (F343) Fused ASD/Main Relay Output circuit.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 6

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





CAUTION: 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 Secondary Air Flow Sensor harness connector and the Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 9

No

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

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





CAUTION: 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 Secondary Air Flow Sensor harness connector and the Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 9

No

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

8. SECONDARY AIR FLOW SENSOR
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Secondary Air Flow 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

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

9. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Secondary Air Flow 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

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