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Troubleshooting and Test Functions
Servo Restart Failed
Servo Restart Failed
The pump motor in the quaternary pump was unable to move into the correct
position for restarting.
When the quaternary pump is switched on, the first step is to switch on the C
phase of the variable reluctance motor. The rotor should move to one of the
C positions. The C position is required for the servo to be able to take control
of the phase sequencing with the commutator. If the rotor is unable to move,
or if the C position cannot be reached, the error message is generated.
Probable Causes • Disconnected or defective cables.
• Blocked active inlet valve.
• Mechanical blockage of the quaternary pump.
• Defective pump drive assembly.
• Defective LPM board.
Suggested Actions ❏ Ensure the pump-assembly cables are not damaged or dirty. Make sure the
cables are connected securely to the LPM board.
❏ Exchange the active inlet valve.
❏ Remove the pump-head assembly. Ensure there is no mechanical blockage
of the pump-head assembly or pump drive assembly.
❏ Exchange the pump drive assembly.
❏ Exchange the LPM board.