Sequence Comm Error — Multi-Compressor Link Fault
The SULLAIR-SEQUENCE-COMM-ERROR (Sullair WS Controller) diesel fault code means: Sequence Comm Error — Multi-Compressor Link Fault. This is a moderate severity code.
- DIY difficulty
- moderate
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Common Symptoms
- WS display shows Sequence Comm Error on sequenced/multi-compressor installations
Probable Causes (Ranked by Likelihood)
- Cable or connection fault between compressors High
- Improper sequence adjustments Moderate
Frequently Asked Questions
Does this stop the compressor?
It breaks coordination between sequenced machines rather than stopping a healthy unit — but until the link is restored, the machines cannot share load the way the installation was designed to.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
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.
Check the sequencing wiring between machines.
Check the sequence settings of ALL compressors in the sequence — one misconfigured unit faults the link.
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.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- Sullair WS Controller User Interface Manual, P/N 02250165-411 (Table 5-1 Troubleshooting Guide)distributor-hosted copy of the official Sullair manualdistributor-hosted copy of an official Sullair factory manual
Commonly Affected Vehicles
- Sullair STATIONARY electric rotary-screw compressors with the WS Controller (including VSD packages)
Related Codes
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