P0418
P0418-SECONDARY AIR INJECTION SYSTEM CONTROL CIRCUIT
- When Monitored:
With the engine running, battery voltage greater than 10.4 volts, and the control circuit active.
- Set Condition:
The Powertrain Control Module (PCM) detects that the control circuit voltage is not within a specified range based on operating conditions.
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. Ignition on, engine not running.
2. With the scan tool, Clear DTCs in the Powertrain Control Module (PCM).
3. With the scan tool, actuate the Secondary Air Flow Pump Relay control to ON or TOGGLE for 5 seconds.
4. With the scan tool, stop the actuation.
5. 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. (F343) FUSED ASD/MAIN RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Remove the Secondary Air Flow Pump Relay.
3. Turn the ignition on.
4. Using a 12-volt test light connected to ground, check the (F343) Fused ASD/Main Relay Output circuit in the Secondary Air Flow 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
- Go To 3
No
- Repair the (F343) Fused ASD/Main Relay Output circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.
3. (K644) SECONDARY AIR PUMP CONTROL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the Powertrain Control Module (PCM).
3. Measure the resistance between ground and the (K644) Secondary Air Pump Control circuit in the Secondary Air Flow Pump Relay connector.
Is the resistance below 100 Ohms?
Yes
- Repair the (K644) Secondary Air Pump Control circuit for a short to ground.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.
No
- Go To 4
4. (K644) SECONDARY AIR PUMP CONTROL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition on.
2. Measure the voltage of the (K644) Secondary Air Pump Control circuit in the Secondary Air Flow Pump Relay connector.
Is there any voltage present?
Yes
- Repair the (K644) Secondary Air Pump Control circuit for a short to voltage.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.
No
- Go To 5
5. (K644) SECONDARY AIR PUMP CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
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.
2. Measure the resistance of the (K644) Secondary Air Pump Control circuit between the Secondary Air Flow Pump Relay connector and the Powertrain Control Module (PCM) harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 6
No
- Repair the (K644) Secondary Air Pump Control circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.
6. SECONDARY AIR FLOW PUMP RELAY ACTUATION
1. Connect the Powertrain Control Module (PCM) connector.
2. Turn the ignition on.
3. With the scan tool, actuate the Secondary Air Flow Pump Relay control to the ON (100%) position.
4. Using a 12-volt test light connected to 12 volts, check the (K644) Secondary Air Pump Control circuit in the Secondary Air Flow Pump Relay connector.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
5. With the scan tool, actuate the Secondary Air Flow Pump Relay control to the OFF (0%) position.
6. Using a 12-volt test light connected to 12 volts, check the (K644) Secondary Air Pump Control circuit in the Secondary Air Flow Pump Relay harness connector.
NOTE: The test light should not be illuminated with the control actuated OFF (0%).
Is the test light illuminated when actuated ON and not illuminated when actuated OFF as described above?
Yes
- Go To 7
No
- Go To 8
7. SECONDARY AIR FLOW PUMP RELAY
1. Turn the ignition off.
2. Inspect the wiring and connectors between the Secondary Air Flow Pump Relay and the Powertrain Control Module (PCM).
3. Look for any chafed, pierced, pinched, or partially broken wires.
4. 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 Flow Pump Relay.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.
8. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Secondary Air Flow 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. 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.