This illustration shows the tilt down limit switch, the sensor PC board, and the three serviceable components of the tilt actuator. Use the table below to isolate the malfunction.

Problem	Required Action
Tilt Up / Down OK, but beeps in full Up position.	Perform Sensor PC board check
Motor runs, but makes grinding noise.	Clean / lube actuator threads. Replace actuator if necessary.
Motor runs, but table does not move.	Inspect / replace motor coupler.
Motor does not run.	Down only - Perform Limit Switch / PCB Harness Test Up only - Perform Sensor PC board check Up or Down - Perform Actuator Motor Test

1.Disconnect harness from J6 on main PC board.

2.Place one meter probe on the common (white).

3.Place other probe on the red wire (see illustration).

With Tilt Down Switch Tripped
Meter Reading	Required Action
OL	Limit switch / harness OK Perform Actuator Motor Test
Less than 10 ohms	Perform Limit Switch Harness Test

With Tilt Down Switch Untripped
Meter Reading	Required Action
OL	Perform Limit Switch Harness Test
Less than 10 ohms	Limit switch / harness OK Perform Actuator Motor Test

1.Unplug the appropriate limit switch harness.

2.Measure continuity.

Actuator Position	Meter Reading Should Be
Actuator Full Up	White to Black - Open White to Red - Closed
Actuator Full Down	White to Black - Closed White to Red - Open
Actuator Midway Point	White to Black - Closed White to Red - Closed

1.Tag and disconnect wires from switch.

2.Place meter probes on COM and NC terminals.

With Switch Tripped
Meter Reading	Required Action
OL	Limit switch OK
Less than 5 ohms	Replace limit switch

With Switch Untripped
Meter Reading	Required Action
OL	Replace limit switch
Less than 5 ohms	Limit switch OK Perform Actuator Motor Test

1.Tag and disconnect tilt actuator wires (J4 and J5).

2.Place meter probes on actuator wires. Check meter reading.

Meter Reading	Required Action
1 to 10 ohms	Actuator motor OK Perform Motor Ground Test
OL or less than 1 ohms	Replace actuator motor.*

1.Place one meter probe on actuator wire (J4).

2.Place other meter probe on PC board ground wire.

3.Check meter reading. Repeat for J5.

Meter Reading	Required Action
OL or more than 1 mega-ohm	Motor harness OK Perform PC Board Test
Less than 1 ohm	Replace actuator motor.

1.Place meter probes on wires at J4 and J5 terminals.

2.Check meter reading while activating Tilt Up / Tilt Down function with foot control.

Meter Reading	Required Action
Approximately 48 VDC	PC board OK
0 VDC	Replace PC board

This illustration shows the tilt down limit switch, the sensor PC board, and the three serviceable components of the tilt actuator. Use the table below to isolate the malfunction.

Problem	Required Action
Tilt Up / Down OK, but beeps in full Up position.	Perform Sensor PC board check
Motor runs, but makes grinding noise.	Clean / lube actuator threads. Replace actuator if necessary.
Motor runs, but table does not move.	Inspect / replace motor coupler.
Motor does not run.	Down only - Perform Limit Switch / PCB Harness Test Up only - Perform Sensor PC board check Up or Down - Perform Actuator Motor Test

1.Disconnect harness from J5 on Motor Control PC board.

2.Place one meter probe on the common (white).

3.Place other probe on the Tilt Down Switch wire (see illustration).

With Tilt Down Switch Tripped
Meter Reading	Required Action
OL	Limit switch / harness OK Perform Actuator Motor Test
Less than 10 ohms	Perform Limit Switch Harness Test

With Tilt Down Switch Untripped
Meter Reading	Required Action
OL	Perform Limit Switch Harness Test
Less than 10 ohms	Limit switch / harness OK Perform Actuator Motor Test

1.Unplug the appropriate limit switch harness.

2.Measure continuity.

Actuator Position	Meter Reading Should Be
Actuator Full Up	White to Black - 3.3 VDC Black to Red - 0 VDC
Actuator Full Down	White to Black - 0 VDC Black to Red - 3.3 VDC
Actuator Midway Point	White to Black - 0 VDC Black to Red - 0 VDC

1.Tag and disconnect wires from switch.

2.Place meter probes on COM and NC terminals.

With Switch Tripped
Meter Reading	Required Action
OL	Limit switch / harness OK
Less than 5 ohms	Replace limit switch

With Switch Untripped
Meter Reading	Required Action
OL	Replace limit switch
Less than 5 ohms	Limit switch OK Perform Actuator Motor Test

1.Disconnect power to the chair.

2.Disconnect Tilt actuator from J2 on PC Board.

3.Set multimeter to Ohms to check resistance.

4.Using a multimeter, place meter probes on actuator wires.

Meter Reading	Required Action
1 to 10 ohms	Actuator motor OK Perform Motor Ground Test
OL or less than 1 ohms	Replace actuator motor

1.Place one meter probe on actuator Black wire (J2).

2.Place other meter probe on PC board ground wire.

3.Check meter reading.

4.Repeat steps for White wire.

Meter Reading	Required Action
OL or more than 1 mega-ohm	Motor harness OK Perform PC Board Test
Less than 1 ohm	Replace actuator motor

1.Place meter probes on Black and White wires at J2 on Motor Control PC board.

2.Check meter reading while activating Tilt Up / Tilt Down function with foot control.

Direction	Meter Reading	Required Action
Tilt Up	Approximately 48 VDC	PC board OK
Any Direction	0 VDC	Replace PC board
Tilt Down	Approximately 16 VDC	PC board OK