Technogym Step 500i SP Service Maintenance Manual page 84

(2) Check the connections, referring to paragraph 2.8. "Wiring".
(3) Place the tester probes across pins 2 and 1 of connector J3 on the HS interface board. The
measured value should be +5 Vdc.
(4) As for step (2) but across pins 1 and 6 of connector CN4 on the display board.
Page 6.28
STEP EXCITE: Service & maintenance manual - rev. 1.4