What causes Haas alarm 1231?

Missing required macro variables in G65 probing call such as feedrate, search distance, or measurement direction parameters. Probing feedrate specified is too fast and exceeds maximum safe probing speed defined in Setting 44 or probe macro limits. Search distance parameter is too large causing probe to exceed travel limits or negative value causing direction conflict. Tool offset number specified in probe macro does not exist or is out of valid range for the machine offset table. Conflicting or incompatible parameter combinations in the probe cycle such as attempting protected move with incompatible measurement mode.

How do I fix Haas alarm 1231?

1. Step 1: Review the probing G-code line that triggered the alarm and verify all required macro variables are present with valid numeric values 2. Step 2: Check probing feedrate parameter and ensure it does not exceed the maximum probe feedrate defined in Setting 44 3. Step 3: Verify search distance parameters are positive values and will not cause the machine to exceed axis travel limits during probe move 4. Step 4: Confirm the tool or work offset number being called in the probe cycle is within the valid range for the control memory 5. Step 5: Cross-reference the probe macro documentation in the Haas Mill or Lathe Operator Manual to verify correct syntax and parameter usage 6. Step 6: Test the probing routine in single block mode with reduced search distance to identify which specific parameter is causing the error

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Haas Controller

Probing · Intermediate · 10 - 30 min

Alarm 1231

Haas Alarm 1231 - Probing G-Code Error

Alarm 1231 occurs when the NGC control's pre-motion validation detects missing, invalid, or conflicting parameters in probing G-code blocks before any axis movement begins. This typically happens with G31 skip function commands, canned probing cycles, or macro-driven probing routines where required parameters like feedrate, axis destinations, or probe input assignments are missing or outside acceptable ranges.

HaasProbingIntermediate10 - 30 min

1231

Haas Alarm 1231 - Probing G-Code Error

Probing G-Code Error

Root Cause Summary

Alarm 1231 occurs when the NGC control's pre-motion validation detects missing, invalid, or conflicting parameters in probing G-code blocks before any axis movement begins. This typically happens with G31 skip function commands, canned probing cycles, or macro-driven probing routines where required parameters like feedrate, axis destinations, or probe input assignments are missing or outside acceptable ranges.

Safety

Probing will not run
⚠️ CRITICAL: Probing cycle will not execute - machine will not perform touch probe operations
Ensure the machine is in a safe state before troubleshooting. Stop the program and disable automatic operation.
Disconnect power to the machine before working on electrical components. Lockout/Tagout procedures should be followed.
Be aware of potential pinch points and moving parts during manual jogging and probing operations.
Wear appropriate personal protective equipment (PPE), such as safety glasses and gloves.
Never bypass or disable safety interlocks.
Ensure the workpiece is securely clamped before running any probing cycles.
Verify the probe is properly mounted and secured to the machine spindle or probe head.

Causes and Fixes

1
Check G31 Block Syntax
Examine the G31 line for proper F-word specification. Ensure feedrate is present and within 0.1-500 IPM range typical for probing operations.
2
Verify Modal Feedrate State
Press CURRENT COMMANDS to view active modal states. If no F-word exists in current block, ensure previous block established valid feedrate modal condition.
3
Test with Explicit Feedrate
Modify G31 block to include explicit feedrate: 'G31 Z-2.0 F10.0' and re-run to confirm parameter validation passes.
Use Setting 44 (Max Probe Feed Rate) to verify your programmed feedrate doesn't exceed machine limits.

DIY Feasiblehigh confidence

Call a technician if:

·Probe hardware failure suspected
·Parameter corruption requiring factory reset
·Macro programming beyond operator skill level

Prevention

Always include explicit feedrate in G31 blocks
Verify probe input signal before running programs
Test probe cycles in single block mode first
Maintain consistent macro variable initialization

Common Mistakes

Forgetting feedrate specification in G31
Using wrong probe input parameter number
Programming probe moves without axis destinations
Not initializing macro variables before probing routines

Related Alarms

1230 1232 1010 1011

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