Philips Intera 1.5T: scans abort as PFINT power LED goes out
What happened
The scanner aborted acquisitions with a power supply front-end electronics failure message, and the left green LED on the PFINT module went dark, as reported in this case.
What was checked
- Measure the DC rails at the labelled terminal block above PFINT and compare them to nominal; in this case the engineers worked to a tolerance of about 5% reported in the case.
- Inspect the front-end power supply (the brick in the filter box under the screens): its output voltages and the cooling fan.
Cause
The 12 V rail from the front-end power supply was running low, so the PFINT module dropped out and the scan aborted; that is what the engineers found in this one case, not a general rule.
What was done
The engineers adjusted the 12 V output of the power supply back into the specified range; the LED lit again and the scanner worked normally afterwards.
Safety
Isolate the supply and allow the PSU capacitors to discharge before opening it, and repeat the electrical safety checks before returning the scanner to clinical use; the magnet stays energised, so keep ferromagnetic tools well clear.
Lesson: Before condemning the module, measure the supply rails at the load — a drifting PSU voltage can shut a subsystem down and look like a dead board.
Covered in the course: MRI 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.