(5) The motors are not plugged into the chair electrical junction box. Test
by visually inspecting the chair electrical junction box to see if the three motors are
(a) If the motors are not plugged in, plug in each one.
(b) If they are plugged in, continue to the next probable cause.
There is a loose connection in the lift electrical junction box.
box for a reading of 115v or 220v, as applicable.
(b) If there is no reading at the chair receptacle on the electrical
junction box, disconnect the chair power cord from the connector at front of lift.
Check terminal 1 (lift connector) for a reading of 115v or 220v, as
(d) If there is no reading, remove the lift motor cover and check for a
loose connection in the lift electrical junction box.
(e) If you find a loose connection, the correct action is to make a
(7) If none of the aforementioned tests proved a probable cause as the
reason for the malfunction, you continue down the list of probable causes using the
testing procedures and corrective actions shown on the troubleshooting guide. The
remaining probable causes are shown below.
(a) A faulty wiring harness.
(b) The assistant or the doctor's manual seal and back switches are
There is a broken chair or sheared pin in the motor sprocket.
(d) There is a bent or broken foot control switch.
(e) There is a faulty motor or capacitor.
The automatic control is not functioning.
(g) There is a faulty relay.