Yale 2350-3 – Vehicle System Manager (VSM) / Main Controller: Front Work Lights Relay (RL4) Driver Output OORH (Out Of Range High)

The main computer detects that the relay for the front work lights is outputting voltage when the controller is actively commanding the circuit to be off. Because work lights are often tied to safety systems on these machines, this fault can trigger an engine shutdown sequence (e.g., shutting off in 30 seconds). Possible causes include: A. Safety switch disconnected, B-D. Short on relay driver output to unswitched/switched battery or another device, E-F. Open circuit in controller driver output, relay coil, or ground, G. Functional failure in the controller.

• Yale and Hyster Forklifts
• Yale VX Series (GLP060VX, GDP155VX, GLC050VX)
• Hyster FT Series

1. 1

   CRITICAL WARNING: Do not use test light probes to check the circuits, as this can destroy the computer. Only use a digital multimeter (DMM)

2. 2

   Check the safety switch wiring and operation

3. 3

   Inspect the wiring harness and connectors associated with the front work lights for broken connections or shorts to battery voltage

4. 4

   Test the RL4 relay coil resistance in the Power Distribution Module (PDM) using a DMM (expected: 80-200 ohms)

5. 5

   Swap the PDM or RL4 relay with a known good test truck to see if the fault follows the component

1. 1

   Turn the truck power to OFF.

2. 2

   Locate and open the cover on the Power Distribution Module (PDM) near the battery.

3. 3

   Identify and remove the Front Work Lights Relay (designated as RL4).

4. 4

   Measure the resistance between the relay coil terminals using a digital multimeter set to the ohms scale.

   If the resistance is out of spec (e.g., < 0.5 ohms), replace the relay.

5. 5

   Check the wiring harness for shorts to the battery or open ground connections using the multimeter.

   Perform this if the relay tests good. Repair any damaged wiring.

6. 6

   Replace the VSM (controller).

   If the wiring and relay are both fully functional, the VSM output pin has likely failed.

7. 7

   Clear the code.

   Safety-related codes often do not automatically clear. You may need a Yale technician to hook up to the truck, reset the code using a maintenance password, or update the truck's software.