Kinetix 6200/6500 fault codes: FLT S33, S43, NODE FLT, INHIBIT

How to read fault messages on the four-character display of Kinetix 6200 (Sercos) and 6500 (EtherNet/IP) control modules, what FL/UL mean, the status indicators, common codes (S10, S16, S23, S33, S43, S61, NODE FLT 06, INHIBIT M05…) and safe fault clearing.

A Kinetix 6200 or Kinetix 6500 (Bulletin 2094) drive shows faults as text on the four-character display of its control module: the display scrolls a message such as FLT S43…MTR FDBK LOSS FL and repeats it until the fault is cleared (2094-UM002I-EN-P, p. 189). The letters before the number give the fault type, the digits that follow give the code (two digits, three for some node codes such as NODE FLT 128), and the words after the dots give a short description. Kinetix 6200 uses the 2094-SE02F Sercos control module; Kinetix 6500 uses the 2094-EN02D EtherNet/IP control module, and some codes exist only on one of the two. Logix Designer shows the same fault as a fault message, for example "Feedback Loss". The full lists are Tables 89–95 (pp. 190–197).

How to read the message

Prefix	Type	What it means
`FLT Sxx`, `FLT Mxx`	Runtime fault	Standard (S) or manufacturer-specific (M) runtime anomaly
`INIT FLT Sxx`, `INIT FLT Mxx`	Initialization fault	Found during power-up, before the drive is enabled
`NODE FLT xx`	Node fault	Stops normal operation of all drives on the power rail
`NODE ALARM xx`	Node alarm	Reported to the controller only, no other action
`INHIBIT Sxx`, `INHIBIT Mxx`	Start inhibit	The drive is prevented from being enabled
`ALARM Sxx`, `ALARM Mxx`	Alarm	Warning reported to the controller only

Source: Table 88 (p. 190). A message ending in FL means a factory-set limit was exceeded; one ending in UL means a user-set limit (p. 190). Many UL codes are marked in the manual as Kinetix 6500 only. With more than one fault, the display shows them in turn, and a higher-priority message hides a lower one, for example a fault hides an alarm (p. 188). When the auxiliary feedback is set up as a feedback-only axis, the message starts with X1: or X2: for the axis (Table 87, p. 189). SAFE FLT codes belong to the Safe Speed Monitoring manual, 2094-RM001 (p. 190).

Status indicators

Indicator	State	Meaning
Drive (Sercos)	Flashing red	Minor fault, recoverable: read the display
Drive (Sercos)	Steady red	Major fault, non-recoverable: read the display
Comm (Sercos)	Off	No communication: loose or broken fiber, or receive and transmit swapped
Comm (Sercos)	Steady red	Duplicate node address
Module / Network (EtherNet/IP)	Flashing red	Recoverable minor fault or connection timeout
Module / Network (EtherNet/IP)	Steady red	Non-recoverable major fault or duplicate IP address
Bus	Flashing green	Bus power present, axis disabled: no 24 V on the Hardware Enable Input or no MSO
Bus	Steady green	Bus power present, axis enabled

Source: Tables 96–101 (pp. 198–199). Bus off with power applied can also mean a follower IAM is not set as "CommonBus Follow" in Logix Designer (p. 198).

Common fault codes

Display	Logix Designer message	Usual causes in the manual	What to check
`FLT S10…INV OVERCURRENT`	IPM Fault	Motor cable or winding shorted, drive too hot, operation above continuous rating, failed component	Continuity of motor cable; turn the motor by hand; fans and space around the drive; reduce accel/decel (p. 191)
`FLT S11…INV OVERTEMP FL`	Inverter Overtemperature	Fan failed, cabinet too hot, RMS current above inverter rating, blocked airflow	Cabinet temperature, airflow, motion profile (p. 191)
`FLT S16…GROUND CURRENT`	Ground Fault	Wiring error, motor ground short, internal fault	Motor and input wiring; test with motor cable removed (p. 191)
`FLT S22…AC POWER LOSS`	AC Power Loss	Axis enabled when three-phase power was removed	Disable the axis before removing power (p. 191)
`FLT S23…AC PHASE LOSS nn`	AC Phase Loss	One or two phases missing; nn = 01 L1, 02 L2, 03 L3	AC voltage on all phases, line control equipment (p. 191)
`FLT S25…PRECHARGE FAILURE`	Pre-charge Failure	DC bus did not reach its level after charging: low AC input	AC voltage on all phases (p. 191)
`FLT S33…BUS UNDERVOLT FL`	Bus Undervoltage	DC bus below 275 V on a 460 V system with power present	Incoming AC level, line drops; disable follower axes before removing power (p. 192)
`FLT S35…BUS OVERVOLT FL`	Bus Overvoltage	Too much regenerated energy; DC bus above 820 V on a 460 V system	Deceleration profile, shunt module, system size (p. 192)
`FLT S43…MTR FDBK LOSS FL`	Feedback Loss	Motor or auxiliary feedback wiring open, shorted or missing	Encoder wiring; run the Hookup test (p. 192)
`FLT S47…MTR ENC SELF TEST nn`	Feedback Self Test	Hiperface encoder reports an internal error (subcode nn)	Feedback cable and shield, motor phasing, noise bonding, firmware; replace the motor if it continues (p. 193)
`FLT S54…POSN ERROR`	Excessive Position Error	Position error limit exceeded: sizing or mechanics	Tuning, following-error limit, mechanics, motor wiring (p. 193)
`FLT S61…ENABLE INPUT`	Drive Enable Input	Hardware enable input dropped while enabled, or software enable with input inactive	Drive Enable input active whenever the drive is enabled through software, or disable the Drive Enable Input fault (p. 194)
`FLT M27…BACKPLANE COMM`	Backplane COM	Noise, poor module connection, faulty module	Cycle control power; with power off, reseat power and control modules (p. 194)
`INIT FLT M23…SERIES MISMATCH`	Series Mismatch on Power Rail	Sercos and EtherNet/IP control modules on the same rail	Replace the mismatched control module (p. 196)
`INIT FLT M24…OPEN SLOT`	Open Power Rail Slot	Missing module or bent pins	Install a slot filler; check pins (p. 196)
`NODE FLT 06…LOST CTRL CONN`	Lost Controller Connection	Ethernet cable faulty or disconnected, controller lost power (Kinetix 6500)	Ethernet connection, controller (p. 196)
`NODE FLT 09…IP ADDRESS`	Duplicate IP Address	Another device on the subnet has the same IP (Kinetix 6500)	Node switch setting (p. 196)
`INHIBIT M05…SAFE TORQUE OFF`	Start Inhibit – Safe Torque Off	The safety function has disabled the power structure	Safety input wiring and safety device state (p. 197)

NODE FLT 01…LATE CTRL UPDATE (Kinetix 6500) means consecutive controller updates were lost; the manual points to network traffic, topology, network equipment and electrical noise (p. 196).

Checks, step by step

Record before resetting: the full display text, which module and axis (X1, X2), and the Drive, Comm or Module/Network and Bus indicators.
Power faults (S22, S23, S25, S33): measure AC on all three phases at the IAM. For S22 and S33, check whether the axis was still enabled when power was removed.
S10 and S16: for S10, with all power and motor connections removed, check continuity from the DC bus to U, V and W (p. 191). For S16, disconnect the motor cable and enable with the current limit set to 0; if the fault clears, the cause is wiring or the motor (p. 191).
Feedback faults (S43, S45, S47, M07): encoder wiring at the motor feedback connector, shield and grounding; run the Hookup test in Logix Designer.
Enable and safety (S61, INHIBIT S01, INHIBIT M05): is 24 V present on the enable input when the axis is enabled, and what state are the safety devices in.
Rail faults (INIT FLT M19, M23, M24): mixed 230 V and 460 V modules, mixed Sercos and EtherNet/IP control modules, or an empty slot (pp. 195–196).
Network faults (Comm red, NODE FLT 06, 09): fiber or Ethernet cables and the node address switches.

How the axis reacts in Logix Designer

Kinetix 6500 exceptions are set in Axis Properties, "Actions": Ignore, Alarm, Fault Status Only, Stop Planner, Stop Drive or Shutdown, and only some exceptions are configurable (p. 202). Kinetix 6200 uses the "Fault Actions" tab; Shutdown also disables axes that use the faulted axis as a cam or gear master and clears AxisHomedStatus (p. 203). INIT FLT codes occur before the drive is enabled, so no stopping behavior applies (p. 202). Check homing after a Shutdown before running again.

Clearing faults safely

Find and correct the cause first; do not defeat the drive fault circuits. Before working on the drive, measure the DC bus voltage or wait the time on the front warning label (p. 187). Clearing a fault can restart the machine: follow the plant's permit and lockout rules.

Shunt module faults stay latched until cleared with MASR, MAFR, MGSR or the HIM, and only after the DC bus has discharged; some conditions need two reset commands (p. 199).
IPIM faults on a Kinetix 6000M system are reset by a fault reset to the IAM (p. 188).
FLT M12…POWER CYCLE FL means DC bus power was cycled too often: no more than two power cycles per minute (p. 194).

When it is hardware

FLT S38…FUSE BLOWN: return the module for repair (p. 192).
FLT M14…CURR FDBK OFFSET: replace the power module (p. 194).
FLT M26…RUNTIME ERROR: replace the module (p. 194).
NODE FLT 02, 03, 128: cycle control power or reset; if it persists, replace the control module, or for NODE FLT 03 subcodes 01 and 02 the power module or power rail (p. 196).

What to record before calling for support

The display text and axis, the indicator states, the catalog numbers of each IAM, AM and control module, the measured AC voltage and what the machine was doing. The older Kinetix 6000 uses E codes on a seven-segment display: see Kinetix 6000 fault codes. For replacement planning, see Kinetix servo drive migration. For an engineer on site: breakdown support.

Frequently asked questions

How do I read a fault on a Kinetix 6200 or 6500 drive?

The four-character display on the control module scrolls the message, for example FLT S43…MTR FDBK LOSS FL, and repeats it until the fault is cleared. The prefix gives the type, the digits the code and the text a short description (2094-UM002I-EN-P, pp. 189–190).

What do FL and UL mean at the end of a Kinetix 6500 fault?

FL means a factory-set limit was exceeded; UL means a user-set limit was exceeded (p. 190). Many UL codes are marked in the manual as Kinetix 6500 only.

What does FLT S33 BUS UNDERVOLT mean on a Kinetix 6200?

With three-phase power present, the DC bus fell below the undervoltage limit, 275 V on a 460 V system. Check the incoming AC level and line drops, and disable follower axes before removing power (p. 192).

Why does a Kinetix 6500 show INHIBIT M05 SAFE TORQUE OFF?

The safety function has disabled the power structure, so the drive cannot be enabled. Check the safety input wiring and the state of the safety devices (p. 197).

Sources

Rockwell Automation, 2094-UM002I-EN-P, Kinetix 6200 and Kinetix 6500 Modular Multi-axis Servo Drives User Manual, 12/2022 — chapter 8 "Troubleshoot the Kinetix 6200 and Kinetix 6500 Drive System" (pp. 187–208)

Read 13 November 2026. This article paraphrases the sources and does not quote them; read the original documents before designing or working on a system. Links open the latest edition in Rockwell's literature library; page numbers refer to the edition cited.