Yale 524230-3 – Vehicle System Manager (VSM) or Power Distribution Module (PDM) / Controller: Rear Work Lights Relay (RL7) Driver Output OORH

The voltage on the relay driver output circuit is higher than expected, indicating a short to battery voltage, an open circuit in the relay coil, or a disconnected circuit on the rear work lights relay line.

• Yale and Hyster Forklifts
• 2005 and newer Yale and Hyster forklifts
• Yale Veracitor VX series (GLP040VX, GLC050VX, GLP155VX)
• Yale electric models (ERP030VT)
• Hyster Fortens (FT) series

1. 1

   Power cycle the truck (OFF for no less than 30 seconds, then ON) to attempt to clear the displayed DTC.

2. 2

   Conduct a visual inspection of all connectors and wiring associated with the rear work lights and the PDM.

3. 3

   Check the rear work lights for defective, shorted, or burnt-out bulbs.

4. 4

   Verify the safety switch (if equipped) is not disconnected.

5. 5

   Check for a short on the relay driver output to unswitched battery, switched battery, or another operated device.

6. 6

   Check for an open circuit in the controller driver output to the relay coil, or the relay coil/ground connection.

1. 1

   Verify the Lights

   Inspect the rear work light bulbs and housings. If a bulb is blown or a housing is smashed and shorting to the frame, replace the light assembly and re-test.

2. 2

   Access the PDM

   Ensure the truck power is OFF. Open the cover on the Power Distribution Module (PDM) and locate the RL7 Relay (Rear Work Lights Relay).

3. 3

   Test the Relay

   Remove the RL7 relay. Set a Digital Multimeter (DMM) to the ohms scale and verify a zero reading. Measure the resistance between the coil terminals of the relay. A typical 12-volt relay coil should read between 80 and 200 ohms. If the resistance is less than 0.5 ohms (shorted) or completely open (infinite resistance), the relay is bad and must be replaced.

4. 4

   Test the Wiring

   If the relay tests good, use your multimeter to check the wiring harness from the PDM to the rear work lights. Look for continuity to ground (shorts) or breaks in the wire (open circuits). Repair any damaged wiring.

5. 5

   Controller Replacement

   If the lights, wiring, and relay all test perfectly fine, the service manual dictates a 'Functional Failure in Controller'. The VSM/PDM will need to be replaced and reprogrammed by a dealer.