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P0412






P0412 - SECONDARY AIR INJECTION SWITCHOVER SOLENOID CIRCUIT





When Monitored and Set Condition

- When Monitored: Continuously with the ignition on.
- Set Condition: An improper voltage level has been detected by the Powertrain Control Module (PCM) on the air pump solenoid control circuit.







Diagnostic Test

1. PRE-DIAGNOSTIC CHECK OUT





NOTE: Always perform diagnostics with a fully charged battery.

NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.

NOTE: Check for applicable TSBs related to the problem.

Turn the ignition on.

With the DRB III(R), read PCM DTCs.

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Repair as necessary.

Perform this procedure prior to symptom diagnosis.

Continue

- Go To 2

2. ACTUATE THE SECONDARY AIR PUMP SWITCHOVER SOLENOID





Turn the ignition on.

With the DRB III(R), actuate the AIRPUMP SWITCHOVER.

Touch the Air Pump Switchover Solenoid with your hand.

Does the Switchover Solenoid click on and off?

Yes

- Go To 7

No

- Go To 3

3. CHECK THE AIR PUMP SWITCHOVER SOLENOID





NOTE: Check the Engine Control Fuse 2 in the Relay Control Module. If it is open, multiple DTCs will be set in the PCM. Determine the cause of the open fuse before continuing using the wiring diagrams/schematics as a guide.

Turn the ignition off.

Disconnect the Air Pump Switchover Solenoid.

NOTE: Check connectors - Clean/repair as necessary.

Turn the ignition on.

With the DRB III(R), actuate the AIRPUMP SWITCHOVER.

Measure the voltage between the Fused Engine Control Relay Output circuit and the Air Pump Switchover Solenoid Control circuit at the Air Pump Switchover Solenoid harness connector.

Does the voltage toggle between B(+) and 0 volts?

Yes

- Replace the Air Pump Switchover Solenoid.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2

No

- Go To 4

4. FUSED ENGINE CONTROL RELAY OUTPUT CIRCUIT OPEN





With the ignition on.

Measure the voltage of the Fused Engine Control Relay Output circuit at the Air Pump Switchover Solenoid harness connector.

Is the voltage above 10 volts?

Yes

- Go To 5

No

- Repair the Fused Engine Control Relay Output circuit for an open.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2

5. AIR PUMP SWITCHOVER SOLENOID CONTROL CIRCUIT OPEN





Turn the ignition off.

Disconnect the PCM C2 harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance of the Air Pump Switchover Solenoid Control circuit from the Air Pump Switchover Solenoid harness connector to the PCM C2 harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go To 6

No

- Repair the Air Pump Switchover Solenoid Control circuit for an open.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2

6. AIR PUMP SWITCHOVER SOLENOID CONTROL CIRCUIT SHORT TO GROUND





With the ignition off.

Measure the resistance between ground and the Air Pump Switchover Solenoid Control circuit at the Air Pump Switchover Solenoid harness connector.

Is the resistance above 100 kohms?

Yes

- Replace and program the Powertrain Control Module.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2

No

- Repair the Air Pump Switchover Solenoid Control circuit for a short to ground.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2

7. INTERMITTENT WIRING AND CONNECTORS

The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.

NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.

NOTE: Check for any Technical Service Bulletins that may apply.

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors specific to this DTC. Wiggle the wires while checking for shorts and open circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2

No

- The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.