GE Brightspeed: patient table jerks, reverses or stalls when moving up
What happened
In normal operation the table moved up erratically: jerky motion, occasional movement down when the up command was given, or no motion at all. In service mode the table worked clearly. No error codes were reported in the case.
What was checked
- If table motion misbehaves only in normal mode but works in service mode, suspect the touch / anti-collision sensors rather than the table drive.
- Inspect the forward touch sensor — the plate on the front upper part of the gantry, below the display — for liquid ingress, dried disinfectant residue and corrosion.
Cause
The engineers found the forward touch sensor plate soaked with disinfectant solutions. The wet sensor fed unstable signals into the table control, which matches the jerking, reversal and stalling in normal mode; this link was reported as probable.
The cause is probable and was not fully confirmed.
What was done
No completed fix was reported in the case. For a touch sensor flooded with disinfectant, remediation is cleaning with careful drying or replacing the sensor — a procedure from the manufacturer's service documentation, done by authorised personnel.
Safety
Before removing gantry covers, isolate the system from the mains and follow the manufacturer's lockout procedure; after any liquid ingress into electronics, run electrical safety tests (including leakage current) before returning the scanner to clinical use.
Lesson: Erratic table motion that clears up in service mode usually points to user-side touch or anti-collision sensors, and disinfectants splashed around the gantry front will eventually find their way into them.
Covered in the course: CT Service — Level 2: Fault-Finding →
Written from an anonymised case shared by service engineers. It is not a manufacturer instruction and grants no authorisation. Independent note; names are trademarks of their owners.