The Problem
A laboratory requested BD Accuri C6 flow cytometer repair after the instrument began reporting negative event values, inconsistent counts, and abnormal liquid-flow readings during acquisition. The behavior continued during water-sample testing, indicating a fault within the fluidics or optical-detection pathway rather than the sample itself.
Diagnostics and Optical Repair
Inspection found a partial obstruction in the hydrodynamic-focusing flow path. Cleaning restored flow through the fine capillary channel, but unusually high background counts remained during water testing. This showed that contamination or damage had also affected the optical-detection assembly.
The complete optical block was replaced, including the flow cell, excitation lasers, and detector components. After reassembly and flushing, sheath pressure, fluid flow, and event counting returned to expected behavior.
SIP Repair and Verification
Follow-up testing found an air leak at the sample injection port. The SIP needle and its O-rings were replaced to stabilize sample flow. Functional testing with water, 6-peak beads, and 8-peak beads produced stable results.
Result
The BD Accuri C6 returned to normal flow and event-counting operation and passed post-repair functional testing. Full operational qualification can be completed separately if required by the laboratory's quality system.
