Yale 523833-3 – VSM (Vehicle System Manager): Glow Plug Relay Driver Output OORH (Out Of Range High)

The system has detected that the output driver feedback is high when the circuit is commanded off. This typically indicates the relay/coil driver output is shorted to system voltage (battery), has an open circuit, the return has an open circuit, or there is a functional failure in the controller.

• Yale and Hyster Forklifts
• VX series
• GC050VX
• GLC050VX

1. 1

   Reset the system by turning the truck power OFF for no less than 30 seconds, then turn it back ON to see if the fault code clears as a transient error.

2. 2

   Visually inspect all connectors and wiring associated with the glow plug relay, the glow plugs, and the VSM for damaged wires, loose connections, or corrosion.

3. 3

   Perform an unswitched voltage check: With truck power OFF, disconnect the glow plug relay and VSM. Measure voltage across the driver pin (+) and battery negative (-). If it equals battery voltage, there is a short to an unswitched battery source.

4. 4

   Perform a switched voltage check: Turn truck power ON and repeat the previous measurement. If it equals battery voltage, there is a short to a switched battery source.

5. 5

   Test the glow plug relay coil for an internal short or open circuit.

6. 6

   Test the glow plugs to ensure they are within specification, as defective glow plugs can trigger relay driver faults.

1. 1

   Repair Wiring

   If the visual inspection or multimeter tests reveal a short to battery voltage or an open circuit in the harness, locate the exact point of failure and repair or replace the affected wiring/connector.

2. 2

   Replace Relay/Glow Plugs

   If the wiring harness tests good but the relay coil is shorted or open, replace the Glow Plug Relay. If the glow plugs test out of specification, replace them.

3. 3

   Replace VSM

   If the wiring, relay, and glow plugs all test perfectly fine and the voltage checks do not indicate a harness short, the VSM has suffered a functional failure on that driver circuit and must be replaced.

4. 4

   Verify Repair

   Reconnect all components, turn the power on, clear the codes, and verify that the sensor/driver outputs are functioning correctly and the code does not return.