Reducing Agent Pump Checking

Reducing Agent Pump Checking

Observe all safety precautions: => [ Safety Precautions ] Safety Precautions

View clean working conditions: => [ Clean Working Conditions ] Clean Working Conditions

Prior to repair work, perform a preliminary check to verify the condition. Refer to => [ Preliminary Check ] Preliminary Check.

• The AdBlue(R) (reducing agent) may irritate skin or eyes. If the fluid comes into contact with skin, rinse/flush the affected area immediately with plenty of water.

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring Diagram.

Test requirements

• The Reducing Agent Pump (V437) and the Reducing Agent Pump Heater (Z103) , are a combined unit and are serviced as an assembly.

• The ignition switched Off.

Start diagnosis

- Disconnect the T8 electrical harness connector on the left rear frame rail near the Reducing Agent Tank assembly.

- Switch the ignition On.

- Using a multimeter, measure the voltage between the T8 electrical harness connector terminal 3 and terminal 2. Refer to Wiring Diagrams for circuit details.

Specified value: Battery voltage

- Using a multimeter, measure the voltage between the T8 electrical harness connector terminal 4 and terminal 2. Refer to Wiring Diagrams for circuit details.

Specified value: near 3.5 V

- Switch the ignition Off.

If all of the specified values were obtained:

- Replace the Reducing Agent Pump (V437) / Reducing Agent Pump Heater (Z103) assembly. Refer to the Repair Information.

If any of the specified values were Not obtained:

Checking wiring

- Remove the Engine Control Module (ECM) (J623). Refer to the Repair Information.

- Using a multimeter, measure the resistance of the circuit between the Reducing Agent Pump (V437) and the Engine Control Module (ECM) (J623). Refer to the applicable wiring diagram.






Specified value: 1.5 ohms Max.

If the specification was Not obtained:

- Check the wires for high resistance, short circuit or open.

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

- Repair as necessary.

If no malfunction is detected in the wiring and the terminal 4 voltage reading was Not OK:

- Replace the Engine Control Module (ECM) (J623). Refer to the Repair Information.

Final procedures

After 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.