SFI SYSTEM, Diagnostic DTC:P0418

DESCRIPTION

Refer to DTC P0412 Click here.

MONITOR DESCRIPTION

The air injection control driver detects open and short circuits according to the voltages of the air pump terminal (VB) and the air switching valve terminal (VV), and transmits diagnostic information as a signal to the ECM.

For a short time after a cold engine start, the ECM transmits command signals to the air injection control driver to drive the air pump and air switching valve assembly.

The air injection control driver transmits an air pump malfunction signal to the ECM if either of the following conditions is met:

• The voltage at the air injection control driver terminal relating to the air pump is low despite the air injection control driver receiving command signals from the ECM to drive the air pump.

• The voltage at the air injection control driver terminal relating to the air pump is high despite the air injection control driver receiving no command signals from the ECM to drive the air pump.

The ECM stored the DTC based on diagnostic signals from the air injection control driver.

WIRING DIAGRAM

Refer to DTC P0412 Click here.

INSPECTION PROCEDURE

• (a) Start the engine and warm it up.

• (b) Turn the ignition switch off.

• (c) Connect the intelligent tester to the DLC3.

• 

  Text in Illustration

  *a	Component with harness connected (ECM)

  (d) Connect oscilloscope probes to the AIDI and E1 terminals of the ECM.

• (e) Turn the ignition switch to ON and turn the intelligent tester on.

• (f) Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Manual Mode / AIR PUMP: ON, ASV: CLOSE.

  Tech Tips

  When Manual Mode is selected, the intelligent tester initialization (atmospheric pressure measurement) is performed automatically. The initialization takes 10 seconds. After the initialization, AIR PUMP and ASV operation can be selected.

• (g) Start the engine.

• (h) Perform the AIR system forced operation while the engine is idling.

• 

  (i) Monitor the air injection control driver voltage output (duty ratio signal).

  Measurement Condition

  Item	Content
  ECM Terminal Name	AIDI - E1
  Tester Range	5 V/DIV., 20 ms/DIV.
  Condition	Idling

• (j) Turn the ignition switch off.

  Note

  
  

  • Secondary Air Injection Check only allows technicians to operate the AIR 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 AIR 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.

  • Performing Secondary Air Injection Check repeatedly may cause damage to the AIR system. If it is necessary to repeat the check, leave an interval of several minutes between System Check operations to prevent the system from overheating.

  • When performing Secondary Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the ignition switch ON or the engine running.

  • Turn the ignition switch off when the Secondary Air Injection Check operation finishes.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (AIR PUMP ASSEMBLY - AIR INJECTION CONTROL DRIVER, AIR INJECTION CONTROL DRIVER - BATTERY)

   
   

   1. Disconnect the cable from the negative (-) battery terminal.

   2. Disconnect the cable from the positive (+) battery terminal.

   3. Disconnect the air pump connector.

   4. Disconnect the air injection control driver connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition A18-2 - A17-2 (VP) Always Below 1 Ω A17-1 (BATT) - Positive battery terminal Always Below 1 Ω A18-4 - Body ground Always Below 1 Ω

      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition A18-2 or A17-2 (VP) - Body ground Always 10 kΩ or higher A17-1 (BATT) or Positive battery terminal - Body ground Always 10 kΩ or higher

   6. Reconnect the air injection control driver connector.

   7. Reconnect the air pump connector.

   8. Reconnect the cable to the positive (+) battery terminal.

   9. Reconnect the cable to the negative (-) battery terminal.

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

2. INSPECT AIR PUMP ASSEMBLY

   
   

   1. Inspect the air pump assembly Click here.

   
   

   NG

   REPLACE AIR PUMP ASSEMBLY Click here

   OK

   REPLACE AIR INJECTION CONTROL DRIVER Click here

3. REPLACE AIR PUMP ASSEMBLY

   
   

   1. Replace the air pump assembly Click here.

   
   

   NEXT

4. CHECK WHETHER DTC OUTPUT RECURS

   
   

   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 and turn the intelligent tester on.

   5. Clear DTCs (if stored)

   6. Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air injection check / Automatic Mode.

   7. Start the engine after the intelligent tester initialization is finished.

   8. Perform the system check operation by pressing Next.

   9. After operating the AIR system, perform the following to confirm the AIR system pending codes: Press the Exit button.

   10. Check pending DTCs.

       OK
       No pending DTC is output.

   11. Turn the ignition switch off.

       Note

       
       

       • 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.

       • Turn the ignition switch off when the Secondary Air Injection Check operation finishes.

   
   

   NG

   REPLACE AIR INJECTION CONTROL DRIVER Click here

   OK

   END