Dtc P0412 Secondary Air Injection System Switching Valve A Circuit

Engine Hybrid System. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
2Tr-Fe Engine Control. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT AIR SWITCHING VALVE ASSEMBLY

CHECK HARNESS AND CONNECTOR (AIR SWITCHING VALVE - BODY GROUND)

CHECK HARNESS AND CONNECTOR (AIR SWITCHING VALVE - AIR INJECTION CONTROL DRIVER)

DTC P0412 Secondary Air Injection System Switching Valve "A" Circuit


DESCRIPTION

The secondary air injection system injects air into the exhaust port of the cylinder head using an electric air pump, starting when the engine is started cold and operating until the catalyst warms up, in order to promote combustion of unburned fuel and decrease the amount of hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gas.

Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.2Tr-Fe Engine Control.Sfi System (W/ Secondary Air Injection System). Dtc P0412 Secondary Air Injection System Switching Valve A Circuit


DTC No.
DTC Detection Condition
Trouble Area
P0412
  1. After cold engine starts, all of following conditions met (1 trip detection logic):
    1. Secondary air injection system not operating (air pump OFF, air switching valve OFF)
    2. Diagnostic signal from air injection control driver 40%
    3. Battery voltage 8 V or more
  1. Open in air switching valve drive circuit
  2. Short between air switching valve drive circuit and +B circuit
  3. Air injection control driver
  4. Air switching valve assembly
  5. ECM
P0412
  1. After cold engine starts, all of following conditions met (1 trip detection logic):
    1. Secondary air injection system operating (air pump ON, air switching valve ON)
    2. Diagnostic signal from air injection control driver 40%
    3. Battery voltage 8 V or more
  1. Short between air switching valve drive circuit and body ground
  2. Air injection control driver
  3. Air switching valve assembly
  4. ECM

MONITOR DESCRIPTION

This DTC indicates an open or short circuit in the circuit containing the air switching valve of the secondary air injection system. The air injection control driver performs diagnosis of the air pump, air switching valve and itself, and sends the results of this diagnosis to the ECM as a duty signal.
When the ECM receives a signal indicating a malfunction in the air pump, air switching valve or air injection control driver, it illuminates the MIL and stores a DTC.

MONITOR STRATEGY


Required Sensors/Components (Main)
Air injection control driver
Required Sensors/Components (Related)
Air switching valve assembly
Frequency of Operation
Once per drive cycle

CONFIRMATION DRIVING PATTERN

NOTICE:
  1. This Secondary Air Injection Check only allows technicians to operate the secondary air injection system for a maximum of 5 seconds.
    Furthermore, the check can only be performed up to 4 times per trip. If the test is repeated, intervals of at least 30 seconds are required between checks.
    While secondary air injection system operation using the intelligent tester is prohibited, the intelligent tester display indicates the prohibition (WAIT or ERROR).
    If ERROR is displayed on the intelligent tester during the test, stop the engine for 10 minutes, and then try again.
  2. Performing the Secondary Air Injection Check repeatedly may cause damage to the secondary air injection system. If necessary, leave an interval of several minutes between System Check operations to prevent the system from overheating.
  3. When performing the Secondary Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the ignition switch turned to ON or the engine running.
  4. Turn the ignition switch off when the Secondary Air Injection Check operation finishes.
  1. Start the engine and warm it up.
  2. Turn the ignition switch off.
  3. Connect the intelligent tester to the DLC3.
  4. Turn the ignition switch to ON.
  5. Turn the intelligent tester on.
  6. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
  7. Turn the ignition switch off and wait for at least 30 seconds.
  8. Turn the ignition switch to ON and turn the intelligent tester on.
  9. Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Automatic Mode.
  10. Start the engine after the intelligent tester initialization is finished.
  11. Perform the System Check operation by pressing ENTER (Next).
  12. Perform the following to confirm the secondary air injection system pending codes: Press the ENTER (Exit).
  13. Check for pending DTCs.
    OK:
    No pending DTC is output.
  14. After the "Secondary Air Injection Check" is completed, check for All Readiness by entering the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  15. Input the DTC: P0412.
  16. Check the DTC judgment result.

    Intelligent Tester Display
    		Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    N/A
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
    HINT:
    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
  17. Turn the ignition switch off.

WIRING DIAGRAM


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.2Tr-Fe Engine Control.Sfi System (W/ Secondary Air Injection System). Dtc P0412 Secondary Air Injection System Switching Valve A Circuit


INSPECTION PROCEDURE

HINT:
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
1.INSPECT AIR SWITCHING VALVE ASSEMBLY

  1. Inspect the air switching valve assembly (HILUX_TGN26 RM00000142V00FX_01_0001.html).



NG
REPLACE AIR SWITCHING VALVE ASSEMBLY (HILUX_TGN26 RM00000142X00FX.html)
OK


2.CHECK HARNESS AND CONNECTOR (AIR SWITCHING VALVE - BODY GROUND)

  1. Disconnect the air switching valve connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    C89-1 - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK HARNESS AND CONNECTOR (AIR SWITCHING VALVE - AIR INJECTION CONTROL DRIVER)

  1. Disconnect the air switching valve connector.

  1. Disconnect the air injection control driver connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    C89-2 - C86-6 (VV)
    		Always
    		Below 1 Ω
    C89-2 or C86-6 (VV) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE AIR INJECTION CONTROL DRIVER (HILUX_TGN26 RM0000030JC028X.html)