Yale 522598-4 – ECU (Engine Control Unit) / ECM (Engine Control Module): LPG Lock Off OORL

Electrical fault in the LPG lock-off valve circuit, specifically that the signal voltage or resistance is lower than the acceptable limit.

• Yale and Hyster Forklifts
• Yale and Hyster LPG/Propane forklifts
• Yale Veracitor VX series
• GLP040SVX
• Units equipped with GM LPG, PSI, or Mazda FE engines

1. 1

   Perform a hard reset by turning the forklift power OFF for no less than 30 seconds, then turn it back ON to see if the code returns.

2. 2

   Perform a visual inspection of all connectors and cables associated with the LPG lock-off valve for pinched wires, corrosion, or disconnected plugs.

3. 3

   Use a multimeter to check for an open circuit or a short to ground between the lock-off valve coil and the ECU wiring harness.

4. 4

   Measure the resistance of the lock-off valve coil to verify if the coil itself has an internal open circuit.

1. 1

   Repair Harness/Connectors

   If the visual inspection or circuit testing reveals damaged wiring, repair or replace the affected section of the harness or connector.

2. 2

   Replace the Lock-Off Valve and Pigtail

   If the wiring tests fine but the coil is faulty, install a new lock-off valve kit that includes a new pigtail plug end.

3. 3

   Splice the New Pigtail

   Cut back the existing wires about 3 inches from the old plug to ensure you are bypassing any hidden wire fatigue near the connector, and splice in the new pigtail.

4. 4

   Clear Codes

   After installation, access the dash display to clear all stored DTCs.

5. 5

   Controller Replacement

   If the wiring is verified good and a new lock-off valve does not resolve the OORL code, replace the ECU/driver as a last resort.