Yale 651-5 – Engine Control Module (ECM): GM Gas Drive Injector 1 Open Circuit, or Cummins-Code 322. See QSB 3.3L Troubleshooting and Repair

The engine controller has detected an open circuit on the #1 cylinder fuel injector circuit. This is typically caused by a fuel injector open circuit (internal coil failure), an injector driver module failure, or a functional failure in the controller.

• Yale and Hyster Forklifts
• Yale and Hyster forklifts (2005 and newer models)
• Yale VX series
• Hyster FT series

1. 1

   Ensure the truck power is OFF and disconnect the battery to discharge capacitors.

2. 2

   Visually inspect Injector 1, its connector, and the wire harness for physical damage, corrosion, or loose terminals.

3. 3

   Disconnect the connector for Injector 1 and perform a resistance test using a multimeter set to Ohms across the injector coil pins. An open circuit (infinite resistance) indicates a faulty injector.

4. 4

   Perform a continuity test on the wiring harness between the injector connector and the ECM to verify there is no break in the signal or supply wires.

5. 5

   If the injector and wiring test good, suspect a failure within the ECM's internal injector driver.

1. 1

   Turn off forklift

   Turn off the forklift and disconnect the battery.

2. 2

   Repair wiring harness

   If the diagnostic checks revealed a broken wire or damaged connector, repair or replace the affected section of the engine wiring harness.

3. 3

   Remove faulty injector

   If the injector coil tested open, relieve the fuel system pressure (if applicable) and remove the faulty #1 fuel injector.

4. 4

   Install new injector

   Install the new fuel injector, ensuring any O-rings or seals are properly seated and lubricated.

5. 5

   Reconnect connector

   Reconnect the injector electrical connector, ensuring it clicks securely into place.

6. 6

   Restore power

   Reconnect the battery and turn the truck power ON.

7. 7

   Clear codes and verify

   Clear the fault codes using the dash display or diagnostic tool, and run the engine to verify the code does not return.

8. 8

   Replace ECM

   If the code persists after verifying the wiring and replacing the injector, replace the Engine Control Module (ECM).