Secondary Air Injection Solenoid Valve, Checking
Secondary Air Injection Solenoid Valve, Checking
Special tools, testers and auxiliary items 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 SB-5 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 ] 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 ohms (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 fuse SB-5 for a short circuit to Ground, high resistance or an open circuit. Refer to Wiring Diagrams for circuit/pin locations.
- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
- If necessary, repair the wiring connection.
If no malfunctions are found in the wiring:
Checking wiring
- Remove the Engine Control Module (ECM) (J623). Refer to the Repair Information.
- 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.
Specified value: 1.5 ohms 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). Refer to the Repair Information.
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 ] Diagnostic Modes 01 - 09.
2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.
3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.