Siemens Symphony: Patient table dead with PTAB communication fault
What happened
The patient table would not power up, and the system pointed to a PTAB communication fault on the table.
What was checked
- In the service mode the switches on the table responded, so it was not a total loss of supply or a fully dead table.
- The A512 board was swapped for a known-good one — the fault stayed, which pointed away from the board itself.
Cause
The engineers found poor contact on the pins of the joystick connector on the PTAB backplane: the solder joint no longer held reliably and broke the communication path.
What was done
The joystick connector on the PTAB backplane was re-soldered, restoring solid contact; after that the table powered up normally and, as reported in the case, the fault did not return.
Safety
De-energise the table and verify absence of voltage before soldering on the backplane, and keep every tool accounted for — the MRI magnet field is always on, so a loose ferrous item near the bore is a serious hazard.
Lesson: A communication fault that makes an assembly look dead can come down to a single connector or solder joint, so check contacts and interconnects before ordering boards.
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.