Fanuc CNC control battery
Replace only with power backed up per the machine procedure so parameters are not lost.
Doosan CNC alarm guide for PUMA, LYNX, DNM, and DVF machines: Fanuc alarms, PMC messages, turret faults, hydraulics, ATC, and spindle checks.
Doosan CNC alarm guide for PUMA, LYNX, DNM, and DVF machines: Fanuc alarms, PMC messages, turret faults, hydraulics, ATC, and spindle checks.
Parts to price first
Replace only with power backed up per the machine procedure so parameters are not lost.
Match inductive or magnetic type, sensing distance, and connector for turret or ATC faults.
Use for servo or spindle feedback faults after checking the exact Fanuc cable number.
Match filter length, micron rating, and housing before replacing a cooljet restriction filter.
Use for spindle orientation, threading, or rigid-tapping faults after confirming the Doosan/Fanuc sensor style.
Match pressure range, thread, and wiring before replacing hydraulic pressure faults on PUMA, LYNX, DNM, or DVF machines.
Doosan CNC machines — PUMA lathes, LYNX lathes, DNM vertical machining centers, and DVF 5-axis — run Fanuc 0i, 18i, 21i, or 31i controls with a Doosan-specific PMC (Programmable Machine Controller) layer on top. When an alarm fires, you’re looking at either a Fanuc servo/system alarm (numbered below 1000) or a Doosan PMC alarm (2000-series). Both types appear on the same Fanuc display and require different diagnostic approaches. This guide covers both.
Doosan CNC alarms split into two categories displayed in different Fanuc screens:
Fanuc CNC Alarms (displayed as alarm code only):
0xx — Program errors (incorrect G-code)1xx — Program format errors4xx — Servo alarms5xx — Servo/spindle communication alarms7xx — Overheat alarms9xx — System alarmsPS alarms — Parameter setting errorsOT alarms — Overtravel (axis exceeded limit)SV alarms — Servo axis alarmsSP alarms — Spindle alarmsDoosan PMC Alarms (2000-series, displayed as text messages): The 2000-series alarms are generated by the Doosan PMC ladder logic. They describe machine-specific faults: hydraulic failures, turret errors, ATC malfunctions, door interlocks, and external device failures.
To display Fanuc alarms: press SYSTEM → ALARM on the Fanuc panel. To display Doosan PMC alarms: press MESSAGE on the Fanuc panel.
For PMC-related alarms (2000-series), access the PMC ladder to see which signal triggered the alarm:
Alarm text: WHETHER EMERGENCY BUTTON IS PRESSED OR OVERTRAVEL OF AXES IS DETECTED, RELEASE EMERGENCY BUTTON AND LIMIT SWITCH FOR OVERTRAVEL CHECK.
Cause: The E-stop circuit has opened. This covers two conditions:
Diagnosis:
E-stop button:
Overtravel limit:
Reset: Release E-stop, clear overtravel if applicable, then press RESET on Fanuc panel.
Alarm text: THE ALARMS OF THE MAIN SPINDLE MOTOR AND SERVO UNIT DETECTED, CHECK ALARM DISPLAY ON THE SERVO UNIT THEN RETRY AFTER POWER OFF-ON.
This alarm is a wrapper — the actual fault is displayed on the spindle drive or servo amplifier itself. Go to the control cabinet and check the alpha/beta amplifier LED display.
Fanuc amplifier display codes (common):
| Drive Display | Meaning |
|---|---|
| 8 | Normal (fan running) |
| A | Overcurrent at output |
| b | Regenerative discharge circuit fault |
| c | Overvoltage on DC link |
| d | Cooling fan failure |
| E | Control power failure |
| F | FSSB disconnect — fiber-optic cable between CNC and amplifier |
| H | Overload on amplifier |
| L | Low voltage on control circuit |
| P | Input power phase missing |
Diagnosis:
Reset: Power off machine at main breaker, wait 30 seconds for capacitors to discharge, power back on.
Alarm text: SPINDLE ROTATION IS ABNORMAL.
Trigger: Spindle encoder feedback does not match commanded speed within the monitoring window.
Causes:
Diagnosis:
Alarm text: SPINDLE SPEED ARRIVAL IS NOT DETECTED WITHIN 7SEC, CHECK SPINDLE SERVO UNIT.
Trigger: The spindle has not reached commanded speed within the 7-second timeout.
Causes:
Diagnosis:
Alarm text: HYD. PUMP MOTOR OVERLOAD IS DETECTED, CHECK OVERLOAD VALUE ON THE THERMAL RELAY AND MOTOR.
Causes:
Diagnosis:
Reset: Press thermal relay reset button, then press machine RESET.
Alarm text: HYD. PRESSURE IS DOWN, CHECK HYD. PRESSURE SWITCH, PRESSURE VALUE AND LEAKAGE OF HYDRAULIC.
Trigger: Hydraulic pressure switch (typically set at 30–50 bar) has not closed within the required time after the hydraulic pump starts.
Causes:
Diagnosis:
Alarm text: TOOL INDEX OVERTIME
Trigger: Turret indexing has not completed within the allotted time.
Causes:
Diagnosis:
Reset: Press RESET, verify chips are cleared, retry T01 command.
Alarm text: TURRET CLAMP SWITCH ERROR
Trigger: Turret clamp and unclamp proximity switches have given conflicting states (both active or neither active at a moment when one should be confirmed).
Causes:
Diagnosis:
Alarm text: TURRET CONTROL UNIT ALARM. CHECK SERVO CONTROL UNIT IN CONTROL CABINET.
Trigger: The servo turret drive amplifier has faulted.
Applies to: Doosan PUMA machines with servo-driven turrets (not hydraulic-indexed).
Diagnosis:
Alarm text: LIMIT SWITCH FOR PROGRAMMABLE TAILSTOCK IS NOT OPERATED WITHIN 5SEC AFTER COMMAND, CHECK SOLENOID VALVES AND LIMIT SWITCHES.
Trigger: The tailstock has been commanded to advance or retract but the confirmation limit switch has not fired within 5 seconds.
Causes:
Diagnosis:
Alarm text: CHUCK IS OPENED DURING THE SPINDLE ROTATION, CHECK HYD. PRESSURE.
Trigger: Hydraulic chuck clamping confirmation switch has dropped out during spindle rotation, indicating the chuck may have opened.
This is a safety-critical alarm. If the chuck actually opens during spindle rotation, the workpiece will be thrown. The alarm is more commonly caused by:
Diagnosis:
Alarm text: PROXIMITY SWITCH FOR CHUCK CLAMP CONFIRM POSITION ERROR, RESET SWITCH POSITION (PX1.M) (PX2.M)
Trigger: Chuck clamp and unclamp proximity switches are both active or inactive when one confirmation is expected.
Diagnosis:
Alarm text: M06 OVERTIME ALARM
Trigger: The M06 tool change cycle has not completed within the timeout period (typically 30–60 seconds depending on ATC type).
Causes:
Diagnosis:
Alarm text: ATC MAGAZINE ROTATION OVERTIME ALARM
Trigger: Magazine rotation (tool carousel) has not completed its rotation within the allotted time.
Causes:
Diagnosis:
Alarm text: ATC DOOR SWITCH ERROR
Trigger: ATC enclosure door is not confirmed in the required position for tool change.
Causes:
Reset: Verify ATC door is physically closed. Check switch alignment.
Alarm text: ATC INTERLOCK ALARM
Trigger: One or more preconditions for ATC operation are not satisfied.
Common interlocks that block ATC:
Diagnosis: Check the PMC ladder for the specific interlock signal that is not satisfied. The ATC interlock ladder net is typically one of the more complex sections — look for the output coil that enables M06 and trace back to all its input conditions.
Alarm text: CHANGER ARM POSITION CHECK ALARM
Trigger: ATC arm is not at its confirmed home position when expected.
Causes:
Diagnosis:
Alarm text: COOLANT & LUB. PUMP MOTOR OVERLOAD OR Q11 FOR SERVO TURRET, CHIP CONVEYOR AND BAR FEEDER OVERLOAD IS DETECTED.
Trigger: Thermal overload on coolant pump, lubrication pump, chip conveyor motor, or bar feeder motor has tripped.
Diagnosis:
Alarm text: LUB. PRESSURE IS DOWN OR LUBRICATION OIL LEVEL IS LOW, CHECK LUB. UNIT AND REPLENISH THE OIL.
Trigger: Lubrication unit pressure switch or low-level switch has activated.
Causes:
Fix: Check lube unit reservoir sight glass. If low, refill with correct oil (typically ISO VG46 or 68 — check machine specification). Press lube unit manual prime button to pre-fill lines, then reset alarm.
Alarm text: COOLANT FILTER CHANGE ALARM
Trigger: Coolant filter restriction sensor or scheduled maintenance counter has activated.
Fix: Replace or clean coolant filter element. Reset filter change counter in machine maintenance menu.
Alarm text: COOLJET LOW PRESSURE OR FILTER BLOCK ALARM
Trigger: High-pressure through-spindle coolant (cooljet) system pressure is below minimum or filter is blocked.
Causes:
Fix: Replace high-pressure coolant filter. Prime pump by running coolant with spindle stopped.
Alarm text: SPINDLE ORIENTATION CONFIRM IS NOT DETECTED WITHIN 10SEC.
Trigger: After an M19 spindle orientation command, the orientation confirmation signal has not been received within 10 seconds.
Causes:
Diagnosis:
Alarm text: SPINDLE TOOL UNCLAMP ALARM
Trigger: After commanding tool unclamp (drawbar release), the tool unclamp confirmation switch has not fired.
Causes:
Diagnosis:
These alarms come from the Fanuc servo software layer, not the Doosan PMC.
Trigger: Axis position has exceeded the soft limit set in Fanuc parameters.
Causes:
Fix:
Trigger: The difference between commanded position and actual feedback position has exceeded the tolerance parameter (typically parameter 1828 — position error limit).
Causes:
Diagnosis:
Trigger: Servo motor thermal load has exceeded limit.
Causes:
Diagnosis:
Trigger: Spindle motor current has exceeded the overload threshold.
Causes:
These are serious system-level alarms indicating hardware failure of the Fanuc control.
Alarm 900/910 (memory errors): Indicate corrupted memory in the Fanuc CNC board. Symptoms include parameter loss, program loss, or strange machine behavior.
Alarm 930 (CPU error): Indicates the main CPU on the Fanuc control has faulted.
For alarms requiring power cycle (servo amplifier faults, 9xx system alarms):
After any power cycle, Doosan machines require axes to return to reference point:
PLEASE MANUAL REF. POINT RETURN) will be active.| Part | Application | Notes |
|---|---|---|
| Servo motor encoder cable | PUMA, LYNX, DNM axes | Most common cause of SV410/SV414 alarms |
| Fanuc A06B servo motor | PUMA, LYNX, DNM | Match alpha/beta series to drive amplifier |
| Servo amplifier (alpha/beta) | All models | Verify model number on drive before ordering |
| Spindle encoder (BZZ sensor) | PUMA, LYNX | Required for orientation, threading, rigid tapping |
| Hydraulic pressure switch | All models | Typical setting 40–50 bar; verify setpoint before replacement |
| Turret proximity switch | PUMA, LYNX | Inductive type; verify sensing distance and cable connector |
| Chuck confirmation switch | PUMA, LYNX | Safety critical; replace with exact equivalent |
| ATC arm home switch | DNM, DVF | Inductive or magnetic depending on ATC type |
| Lubrication unit oil level switch | All models | Float type; replace if float is stuck |
| Fanuc CNC control battery | All Fanuc models | 3V lithium; replace every 3–5 years or when low battery alarm appears |
| Rotary hydraulic union | PUMA, LYNX (chuck) | Replace if chuck pressure fluctuates during spindle rotation |
| Through-spindle coolant filter | DNM, DVF with cooljet | Replace when Alarm 2074 appears |
Doosan CNC machines (Puma lathes, DNM machining centers, Lynx lathes) primarily use Fanuc 0iF, 31iA, and 31iB controls. Alarms come from two sources: Fanuc NC alarms and Doosan PLC macro alarms.
| Alarm Range | Source |
|---|---|
| 1–999 | Fanuc NC alarms |
| 1000–1999 | Fanuc Servo alarms |
| 5000–5999 | Fanuc system alarms |
| 9001–9999 | Doosan PLC (PMC) macro alarms — machine-specific |
| Alarm | Meaning | Quick Fix |
|---|---|---|
| 400 — Servo Alarm | Servo drive fault | Check drive and motor |
| 460 — Spindle Speed Error | Spindle speed deviation | Check belt, drive, and encoder |
| 700 — Overheat | Control unit thermal alarm | Check cabinet cooling |
| 1000-series | Servo axis faults | Check amplifier and motor |
| 9001 — Hydraulic Pressure | Hydraulic pressure low | Check hydraulic pump and pressure |
| 9050 — Spindle Oil | Spindle oil level low | Check spindle oil sight glass |
| 9100 — ATC Fault | Tool changer alarm | Inspect ATC mechanism |
| 9200 — Turret Fault | Turret indexing fault | Check turret motor and position |
Doosan machines (especially Puma lathes) use a hydraulic system for the chuck, tailstock, and turret. If hydraulic pressure drops below the setpoint, this alarm fires. Check:
The spindle lubrication oil level is below the minimum. Check the spindle lubrication reservoir (typically at the top of the headstock or separate oil mist unit). Add the correct spindle oil grade. Do not run the machine on low spindle oil — it damages spindle bearings.
The automatic tool changer did not complete its indexing cycle. Check for:
| Feature | Puma (Lathe) | DNM (Machining Center) |
|---|---|---|
| Typical turret | 12-station hydraulic | 30-tool BT40 ATC |
| Hydraulic system | Yes | Limited or no |
| Spindle configuration | Horizontal, C-axis | Vertical |
| Common 9xxx alarms | Chuck, turret, tailstock | ATC, pallet, tool length |
PMC alarms on Doosan machines show as “PMC ALARM” followed by the alarm number. To see the alarm message:
Before ordering, match the machine-control part to the model number, electrical rating, and failure symptom:
Find replacement parts for Doosan CNC machines on Amazon by the failed subsystem:
Fanuc alarms come from the CNC, servo, spindle, or system layer. Doosan PMC alarms come from the machine ladder and describe machine functions such as hydraulics, turret, ATC, door, or external-device faults.
Use the Fanuc alarm history screen for CNC events and the PMC message history for Doosan machine alarms. Record the first alarm because later alarms may only be consequences.
Alarm 2001 points to an open emergency-stop or overtravel condition. Release all E-stop buttons, check overtravel switches, and verify the E-stop relay before resetting.