SULLAIR-E-STOP critical Sullair WS Controller

E-Stop Push Button Active

The SULLAIR-E-STOP (Sullair WS Controller) diesel fault code means: E-Stop Push Button Active. This is a critical severity code.

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

  • WS display shows E-Stop Push Button; machine will not run

Probable Causes (Ranked by Likelihood)

  • Emergency stop button pressed / latched High
  • Faulty E-Stop button or wiring 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. Release (twist or pull) the emergency stop button, then clear with STOP.

  3. If no button is engaged, check the E-Stop button and its wiring — an open in that circuit reads as an active stop.

  4. 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

The button is out but the message stays — why?

The controller sees the E-Stop circuit open. If the button is genuinely released, the button contacts or the wiring between it and the controller have failed open, and that circuit needs checking end to end.

Sources

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

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