SULLAIR-AUX-MOTOR-OVERLOAD serious Sullair WS Controller

Aux. Motor Overload — Fan/Pump Motor Tripped

The SULLAIR-AUX-MOTOR-OVERLOAD (Sullair WS Controller) diesel fault code means: Aux. Motor Overload — Fan/Pump Motor Tripped. This is a serious severity code.

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Keep driving?
Yes, but fix soon
DIY difficulty
moderate
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Common Symptoms

  • WS display shows Aux. Motor Overload

Probable Causes (Ranked by Likelihood)

  • Auxiliary motor (cooling fan, fluid pump or other) tripped its overload High
  • Loose connections Moderate
  • Motor starter contact fault Moderate
  • Low line voltage Moderate

Step-by-Step Diagnostic Procedure

  1. The WS Controller is fitted to Sullair STATIONARY electric shop compressors. Portable towable Sullair units (185-class and similar) use different engine-driven controls and a different fault system — this page does not apply to them.

  2. Reset the auxiliary overload after the element cools.

  3. Verify correct motor amps and check for loose connections.

  4. Check the motor starter contact for proper operation, and line voltage (consult the power company if low).

  5. Per the factory manual: after resolving a fault condition, press the STOP pad to clear the FAULTED state. If the problem persists after the recommended checks, consult your Sullair distributor or factory service.

Frequently Asked Questions

Which motor is the auxiliary?

Any motor other than the main drive — typically the cooling fan or fluid pump. Because a stopped fan quickly becomes an over-temperature fault, do not run the machine with this unresolved.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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