Ultra Chair Positioning Potentiometer Test and Repair
Check Continuity (Ohms)
Unplug chair power cord before removing covers or working on chair. Failure to comply could result in personal injury.
1.Disconnect power to chair and remove upholstery or covers whichever is applicable to access potentiometer Refer to: Base Potentiometer and Back Potentiometer.
2.Set VOM on resistance (ohms) for a scale that can read up to 6K ohms.
Testing Potentiometer - Check Continuity (Ohms)
3.After removing plug connector, place meter probes, Item 1, on outside leads (A) of potentiometer, Item 2, for total resistance. Reading should be 4K to 6K (ohms). Any reading outside this or if no continuity reading is present, replace potentiometer.
4.Move one meter probe to middle lead (B) on potentiometer.
5.Slowly rotate potentiometer shaft fully one direction and then back the other.
Meter should show a smooth increase or decrease in resistance. If reading becomes erratic replace potentiometer Refer to:Base Potentiometer and Back Potentiometer.
Check Voltage (VDC)
1.Remove seat upholstery or appropriate covers to access back or base potentiometer. Refer to:Base Potentiometer and Back Potentiometer.
Use caution to prevent electrical shock with chair plugged into outlet. Electrical components and connections are exposed.
2.Plug chair into outlet.
3.Set meter to read voltage DC on scale appropriate to read approximately 5 VDC.
4.Place meter probes, Items 1, on two outside leads (A) of potentiometer, Item 2.
Reading should be approximately 5 VDC (±1 VDC). If voltage reading is zero (0), leads are broken in wire harness between potentiometer and P.C. board or P.C. is not working correctly. Refer to: Troubleshooting.
Testing Potentiometer - Check Voltage (VDC)
