Massey Ferguson E 9170 (6) – Engine Control Unit (ECU): Lift pump control (ECU), short circuit to earth

The Engine Control Unit (ECU) has detected an open circuit in the electrical system for the fuel lift pump control, indicating a break in the electrical path to the lift pump. This could be due to a disconnected wire, a faulty connection, a failed relay, or a break in the internal wiring of the lift pump itself. An open circuit will prevent the lift pump from operating, stopping fuel from being drawn from the tank to the high-pressure fuel system and leading to a lack of fuel supply to the engine.

• 8600 Series
• 3600 Series
• 5400 Series
• 6400 Series
• 7400 Series
• 8400 Series
• 5465
• 5475
• 6475
• 6480
• 6490

1. 1

   Visually inspect the wiring harness running from the Engine ECU to the electric fuel lift pump for chafed, pinched, or melted wire insulation touching the chassis (earth).

2. 2

   Perform component vs. harness isolation: Disconnect the electrical connector at the fuel lift pump, turn the ignition on, and check active fault codes. If the code changes to E 9170 (5) [open circuit], the short is internal to the pump. If E 9170 (6) remains, the short is in the wiring harness.

3. 3

   With the battery disconnected and both the ECU and lift pump unplugged, use a digital multimeter to test the lift pump control wire for continuity to ground.

1. 1

   Disconnect battery

   If the wiring harness is shorted: Disconnect the negative battery terminal.

2. 2

   Trace wire

   Trace the lift pump control wire back to the ECU to locate the shorted area.

3. 3

   Repair or replace harness

   Repair the damaged wire using proper solder and heat-shrink tubing, or replace the damaged harness section.

4. 4

   Secure harness

   Secure the harness away from sharp metal edges or high-heat sources to prevent recurrence.

5. 5

   Disconnect battery

   If the lift pump is internally shorted: Disconnect the negative battery terminal.

6. 6

   Locate pump

   Locate the electric fuel lift pump assembly on the engine.

7. 7

   Place catch pan

   Place a catch pan underneath to catch residual diesel fuel.

8. 8

   Disconnect fuel lines

   Disconnect the fuel inlet and outlet lines from the pump.

9. 9

   Remove pump

   Unbolt the lift pump from its mounting bracket and remove it.

10. 10

    Install new pump

    Install the new electric fuel lift pump and tighten the mounting hardware.

11. 11

    Reconnect lines and connector

    Reconnect the fuel lines and plug in the electrical connector.

12. 12

    Prime fuel system

    Reconnect the battery. Turn the ignition key to the ON position to prime the fuel system and check for leaks.

13. 13

    Clear codes

    Clear the fault codes via the diagnostic menu and start the engine to verify the code does not return.