Secondary Air Injection Pump Motor, Checking

Special Tools And Workshop Equipment Required 

• Multimeter
• Wiring diagram.

Test Requirements 

• The Secondary Air Injection (AIR) Pump Relay --J299-- fuse 27 in Fuse Box B 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 .

Start Diagnosis 

-- Disconnect the secondary air injection hose.

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

Checking voltage

-- Start the engine.

-- Using a multimeter, check the Secondary Air Injection (AIR) Pump Motor --V101-- electrical harness connector terminals 1 to 2 for voltage.

Specified Value: Battery Voltage. 

-- Switch the ignition off.

If the specified value was Not obtained:

-- Switch the ignition on

-- Using a multimeter, check the Secondary Air Injection (AIR) Pump Motor --V101-- electrical harness connector terminal 2 to Ground (GND).

Specified Value: Battery Voltage. 

If the specified value was Not obtained:

-- Check the wiring connection from the Secondary Air Injection (AIR) Pump Relay --J299-- socket 2 (relay terminal 87) to the Secondary Air Injection (AIR) Pump Motor --V101-- electrical harness connector terminal 2 for an open circuit or a short circuit.

-- Check the wiring connections for damage, corrosion, loose or broken terminals or an open fuse. Refer to the wiring diagram.

-- If necessary, repair the faulty wiring connection, replace fuse if needed.

If the wiring has no fault, the fuse is not open and voltage is Not present:

Replace the Secondary Air Injection (AIR) Pump Relay --J299--

If the specified value was obtained:

Checking Ground (GND)

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

Specified Value: 1.5 Ω Max. 

If the specified value was Not obtained:

-- Check the wiring for an open or high resistance.

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

-- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring and voltage supply was OK:

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

-- Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .

-- Perform a road test to verify repair.

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 .
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 .