XNX Honeywell Gas Detector Fault Codes
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This page lists the fault messages shown by the Honeywell Analytics XNX Universal Transmitter (XNX) and common connected sensor types (ECC, mV, Optima, and Searchline Excel). Use the “Action for Resolution” column as a first-pass troubleshooting guide.
| Fault Code | Fault Message | Applicable Sensors | Latching? | Diagnostic Frequency | Event History Data | Action for Resolution |
|---|---|---|---|---|---|---|
| F101 | Unexpected Sensor Reset | All | Non-latching | ECC & mV: main loop ×2; Optima & Excel: 2 seconds | Note 2 (Optima/Excel may also show sensor fault/warning code) | If repeated, check supply voltage, check cable loop impedance, check terminal connections. |
| F103 | XNX Temperature Error | All | Non-latching | 2 seconds | XNX temperature (°C) | Check for heat sources; add sunshade/protection; relocate transmitter; verify temperature in Info → Transmitter Status. |
| F104 | XNX 24 VDC Supply Bad | All | Non-latching | 2 seconds | XNX supply voltage ×1000 | Check the 24 V power wiring to XNX and the power supply operation. |
| F105 | 3.3 VDC Supply Bad on XNX, personality board, or option board | All | Non-latching | 2 seconds | 1 = XNX, 2 = Personality board, 3 = Option board | Check Transmitter Status. |
| F106 | XNX Real Time Clock Failure | All | Non-latching | 2 seconds | Total seconds since Jan 1, 1970 | Clock may be incorrectly set or battery failed (note: clock stops on Jan 1, 2036). |
| F107 | XNX Internal Failure (RAM, ROM, EEPROM, Opcode) | All | Non-latching (except EEPROM error) | At power-up and every 8 hours | Note 3 | Contact Honeywell Analytics Service Department. |
| F108 | XNX mA Output Loop Failure | All | Latching | 2 seconds | mA output error (measured mA − set mA) | Check mA output wiring and verify switches S1/S2. If not resolved quickly, F149 may also occur; when the cause is fixed, both faults clear. |
| F109 | Simulated Warning/Fault | All | Non-latching | Enabled by user | 0 | Alarm/fault reset clears all simulation. |
| F110 | Sensor software mismatch | Optima | Latching | Checked at power-up only | Sensor firmware version ×10 | Contact Honeywell Analytics Service Department. |
| F111 | Negative Drift | ECC, mV | Non-latching | 2 seconds | Raw gas concentration | Check for external interference; perform zero calibration; if persists with no interference, replace sensor. |
| F111 | Negative Drift (may indicate a failed IR sensor) | Optima, Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check for external interference; perform zero calibration; if persists with no interference, replace sensor. |
| F112 | Sensor 24 VDC Supply Bad | Optima, Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check 24 V supply wiring to transmitter and wiring between transmitter and Optima/Excel. |
| F113 | Sensor Internal 5V Power Supply Defect | Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Remove and return to Honeywell for repair. |
| F114 | Sensor Internal Lamp Issue | Optima | Latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Remove and return to Honeywell for repair. |
| F116 | Sensor Internal Failure | Optima, Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Remove and return to Honeywell for repair. |
| F117 | Sensor Loop Failure (sensor is losing/has lost mA output) | Optima, Excel | Latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check supply voltage stability; check wiring and loop impedance; verify switches S3/S4 (power down before changing). After fixing, perform a soft reset to clear and restore Calibration menu access. |
| F118 | Sensor Real Time Clock issue | Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Reset Excel date/time; recycle Excel power; confirm retention; if not retained, return to Honeywell for repair. |
| F119 | Cartridge Internal Electrical Failure | ECC, mV | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Note 5 | Check cartridge connections and operation; replace cartridge; replace personality board if needed. |
| F120 | No Sensor | ECC, mV, Optima, Excel | Non-latching | 2 seconds | Note 2 | Indicates loss of comms. Verify part number vs installed hardware and check wiring between sensor and XNX. |
| F121 | Wrong Cartridge / error loading sensor parameters | All | Non-latching | At power-up and when cartridge is changed | 0 | Contact Honeywell Analytics Service Department. |
| F122 | General Diagnostics | Optima, Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check connections/operation; replace sensor; replace personality board if needed. |
| F123 | Sensor Temperature Error | Optima | Non-latching | (frequency controlled by sensor) | Sensor fault or warning code | Check heat sources; add sunshade/protection; relocate; verify temperature in Info → Sensor Status. |
| F123 | Sensor Temperature Error | Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check heat sources; add sunshade/protection; relocate; verify temperature in Info → Sensor Status. |
| F123 | Sensor Temperature Error | ECC | Non-latching | 2 seconds | Sensor temperature (°C) | Check heat sources; add sunshade/protection; relocate; verify temperature in Info → Sensor Status. |
| F125 | Calibration Required | All | Non-latching | 2 seconds | Days remaining until calibration expires (negative = days expired) | Span calibration interval exceeded. Perform a successful span calibration to clear. |
| F126 | Sensor Path Obscured | Optima | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check for external interference and dirty windows. |
| F127 | Beam Block | Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check for obstructions; check windows; check Excel alignment. |
| F128 | Sensor Installation Not Complete | Excel | Non-latching | XNX polls sensor every 2 seconds (frequency controlled by sensor) | Sensor fault or warning code | Check Excel alignment and perform a zero calibration. |
| F130 | Option Communication Failure | All | Non-latching | 2 seconds | Option module ID: 0=None, 1=Foundation Fieldbus, 2=Modbus, 3=Relay | Verify installed option matches XNX part number. If changed, set up in Information → Transmitter Data per manual. |
| F133 | Not used | — | — | — | — | — |
| F143 | Stabilization Timeout | All | Latching | 2 seconds | Warm-up time (seconds ×100) | Cycle power; contact Honeywell Analytics Service Department if problem persists. |
| F145 | Reflex Failure | ECC | Non-latching | Dependent on sensor (typically 8 hours); once detected: every 15 minutes | nA/mV | ECC sensor no longer functioning properly. Replace sensor. |
| F146 | Unknown Sensor Failure | Optima, Excel | Non-latching | 2 seconds | Sensor fault or warning code | Contact Honeywell Analytics Service Department. |
| F148 | Internal option board hardware failure | All | Non-latching | 2 seconds | Option board error status (Note 6) | Contact Honeywell Analytics Service Department. |
| F149 | Internal 4–20 mA monitoring circuit communication failure | All | Non-latching | 3.366 seconds | 0 | Contact Honeywell Analytics Service Department. |
| F150 | mA Output Monitor Communications Watchdog Error | All | Non-latching | 138 μs | Communication error count | Contact Honeywell Analytics Service Department. |
| F151 | Sensor Module Type Changed | ECC | Non-latching | 2 seconds | Module type: 0=None, 1=ECC, 2=mV, 3=Excel, 4=Optima, 5=Generic mA | For ECC: run “Accept New Sensor”; if persists contact Honeywell. For others: contact Honeywell. |
| F152 | Option Module Configuration Error | All | Latching | At power-up or every 125 ms when no option board detected | Option module ID: 0=None, 1=Foundation Fieldbus, 2=Modbus, 3=Relay | Confirm option installed correctly; reconfigure unit. |
| F153 | Signal/Data mismatch error on IR personality | Optima, Excel | Non-latching | 2 seconds | Digital sensor reading | Check wiring (especially the white wire between XNX and Optima/Excel). Power cycle required to reset after fixing. |
| F154 | mA Input Diagnostic Failure | Optima, Excel | Latching | 5 minutes after power-up and then every 8 hours | Input mA | Contact Honeywell Analytics Service Department. |
| F155 | Generic mA Sensor Type Error | Generic mA | Non-latching | 2 seconds | Input mA | Input < 3 mA. Check wiring; verify S3/S4; if OK, replace sensor. |
| F156 | mV Current Control Failure | mV | Non-latching | Main loop ×16 | Constant current A/D input mV | Verify correct mV sensor type selection; check wiring; if OK, replace sensor. |
| F157 | Sensor Drift Fault | ECC, mV | Non-latching | 2 seconds | Current baseline | Perform zero calibration; if persists, replace sensor. |
| F158 | Sensor/Personality Part Number mismatch | All | Non-latching | ECC & mV: main loop ×2; Optima & Excel: 2 seconds | Entire personality part # | Verify installed option matches XNX part number; check wiring to Optima/Excel. |
| F159 | Option Part Number Mismatch | All | Non-latching | At power-up or every 125 ms when no option board detected | Entire option part # | Verify installed option matches XNX part number; check wiring to Optima/Excel. |
| F160 | Hardware Diagnostic Failure | ECC, mV | Non-latching | Main loop ×2 | Gain1 high byte, Gain2 low byte | Replace defective EC cartridge or mV personality board. |
| F161 | mA Input Indicates Fault | Optima, Excel | Non-latching | 1 second | Input mA | Input below 1 mA indicates sensor fault. Check event history for additional faults; if none, check wiring and verify S3/S4. |
| F162 | Error reloading safety critical RAM block | All | Non-latching | 2 seconds | Note 3 | Contact Honeywell Analytics Service Department. |
| F163 | Interrupt integrity fault | All | Non-latching | Main loop | Note 3 | XNX will reset if more than 600,000 successive errors occur. |
| F164 | mV sensor failure | mV | Latching | 1 second | Sensor fault or warning code | Check connections/operation; replace sensor; replace personality board if needed. |
| F165 | mA Calibration failure | All | Latching | 2 seconds | Bitfield indicating which DAC/ADC point failed | Calibration failed and discarded. Check loop resistance; repeat 4–20 mA calibration. Clears after a successful calibration. |
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