Secondary Air Injection Solenoid Valve, Checking

Special Tools And Workshop Equipment Required 

• Multimeter.
• Wiring diagram.

Test Requirements 

• The Secondary Air Injection (SAI) Solenoid Valve --N112-- fuse OK.
• The Engine Control Module (ECM) Power Supply Relay -J271- and the Fuel Pump Relay -J17- fuse OK.
• Battery voltage at least 12.5 V.
• All electrical consumers switched off (radiator fan must NOT run during test).
• A/C switched off.
• The ignition switched OFF.

Test Procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK .

Start Diagnosis 

Procedure 

-- Disconnect the Secondary Air Injection (SAI) Solenoid Valve --N112-- electrical harness connector.

Checking internal resistance

-- Using a multimeter, check the Secondary Air Injection (SAI) Solenoid Valve --N112-- terminals 1 to 2 for resistance.

Specified Value: 3.5 - 8.5 Ω (At Approx. 20 °C) 

If the specified value was Not obtained:

-- Replace the Secondary Air Injection (SAI) Solenoid Valve --N112--.

If The Specified Value Was Obtained: 

Checking voltage supply

Start the engine.

-- Using a multimeter, check the Secondary Air Injection (SAI) Solenoid Valve --N112-- electrical connector terminal 1 to Ground for voltage.

Specified Value: Battery Voltage. 

Switch the ignition OFF.

If the specified value was Not obtained:

-- Check the wiring from the Secondary Air Injection (SAI) Solenoid Valve --N112-- electrical connector terminal 1 to the Secondary Air Injection (SAI) Pump Relay -J299- or Fuel Pump Relay -J17- for a short circuit to Ground, or an open circuit. Refer to Appropriate System Diagrams for circuit layout/pin locations.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- If necessary, repair the wiring connection.

If The Specified Value Was Obtained: 

Checking wiring

-- Remove the Engine Control Module (ECM) -J623-.

-- Using a multimeter, check the Secondary Air Injection (SAI) Solenoid Valve --N112-- electrical harness connector terminal 2 to the Engine Control Module (ECM) -J623- electrical harness connector T60 for an open circuit.

Secondary Air Injection (SAI) Solenoid Valve --N112-- electrical harness connector terminal:	Engine Control Module (ECM) -J623- electrical connector T60 terminal:
2	48

Specified Value: 1.5 Ω Max. 

If the specified value was Not obtained: 

-- Check the wiring for an open, high resistance or short to ground.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring: 

-- Replace the Engine Control Module (ECM) -J623-.

Final Procedures 

After the repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .