Air Injection Pump: Testing and Inspection

Diagnostic Procedures

Secondary Air Injection Pump Motor, Checking

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• The Secondary Air Injection (SAI) Pump Relay (-J299- ) fuse is OK.

• The Motronic Engine Control Module (ECM) Power Supply Relay (J271) 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

- Disconnect the Secondary Air Injection (SAI) Pump Motor (-V101-) electrical harness connector.

• The Secondary Air Injection system ONLY operates at initial start-up when the coolant temperature is near ambient temperature. The pump will operate for approximately 20 to 45 seconds and will NOT run again unless coolant temperature and ambient temperature are within 3° C of each other.

Checking voltage

- Connect a multimeter to the Secondary Air Injection (SAI) Pump Motor (-V101-) electrical harness connector terminals 1 to 2.

- Start the engine and read the voltage on the multimeter.

- Switch the ignition OFF.

Specified value: Battery voltage.

If the specified value was obtained:

- Replace Secondary Air Injection (SAI) Pump Motor (-V101-).

If the specified value was Not obtained:

- Using a multimeter, check the Secondary Air Injection (SAI) Pump Motor (-V101-) electrical harness connector terminal 1 to Ground.

Specified value: 0.5 ohms or less.

If the specified value was Not obtained:

- Check the ground circuit for an open or high resistance. Refer to Wiring Diagrams.

- Repair the circuit as necessary.

If the specified value was obtained:

- Using a multimeter, check the Secondary Air Injection (SAI) Pump Motor (-V101-) electrical harness connector terminal 2 to the Secondary Air Injection (SAI) Pump Relay (-J299-) connector terminal 2 (relay 87).

Specified value: 0.5 ohms or less.

If the specified value was Not obtained:

- Check the voltage supply circuit between the Secondary Air Injection (SAI) Pump Relay (-J299-) and the Secondary Air Injection (SAI) Pump Motor (-V101-) for an open or high resistance. Refer to Wiring Diagrams.

- Repair the circuit as necessary.

If the specified value was obtained:

- Perform the Secondary Air Injection Pump Relay test to find cause of no voltage to the SAI pump motor.

Final procedures

After the repair work, the work steps below 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.