Yale 676-3 – VSM (Vehicle System Manager): Glow Plug Relay Driver Output OORH (Out Of Range High)

The controller is detecting a higher-than-expected voltage on the glow plug relay driver circuit. This typically means the relay/coil driver output is shorted to the battery, or there is an open circuit in the driver output or return lines.

• Yale and Hyster Forklifts
• Yale VX Series
• GDP060VX
• GPD20SVX
• GC050VX
• Hyster FT Series
• H3.5FT

1. 1

   Ensure the truck power is completely OFF before beginning diagnostics.

2. 2

   Set a Digital Multimeter (DMM) to the ohms scale and verify a zero reading.

3. 3

   Measure the resistance of the device driver wire between the glow plug relay connector and the VSM connector (should be less than 0.5 ohms). Higher resistance indicates an open circuit.

4. 4

   Check the relay/coil driver output circuit for a short to battery voltage.

5. 5

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

1. 1

   Repair Wiring

   If the diagnostic checks reveal a short to the battery voltage or an open circuit in the wiring harness between the relay and the VSM, repair or replace the affected wiring.

2. 2

   Replace the Relay

   If the wiring is intact but the relay coil is shorted to ground, has high resistance, or fails to click when the control side is grounded, replace the Glow Plug Relay.

3. 3

   Test/Replace the VSM

   If the wiring and the relay are both in good working order, the fault lies within the controller's output driver. Test the VSM driver output pins; if the driver is faulty or missing the output signal, the VSM (Vehicle System Manager) must be replaced.