230-0459

Check Battery Status in Diagnostics

Navigate to MOD function → Diagnosis → TNC → Battery and check voltage readings. Normal voltage should be above 3.0V for lithium batteries.

Battery voltage below 2.8V will cause intermittent S-RAM corruption issues

Verify S-RAM Integrity

Access MOD → Diagnosis → TNC → Memory and run S-RAM test to identify corrupted memory sectors.

Do not power cycle the machine during S-RAM diagnostics

Replace Battery and Clear S-RAM

Replace backup battery, then execute MOD → Machine Parameters → Clear S-RAM and perform fresh encoder reference run on affected axis.

Always perform battery replacement with machine powered on to maintain S-RAM contents

Check EnDat Communication Status

Navigate to MOD → Diagnosis → Axis → EnDat and monitor communication error counters for the affected axis. Look for CRC errors or timeout values.

Error counts should remain at zero during normal operation

Inspect Encoder Cable and Connections

Check encoder cable for damage, proper shielding, and secure connections at both encoder and TNC ends. Verify cable routing away from power cables.

Always power down before disconnecting encoder cables to prevent damage

Test Encoder Signal Quality

Use MOD → Diagnosis → Axis → Position to monitor encoder signals and verify clean position feedback without dropouts or noise.

Oscilloscope verification of EnDat signals may be needed for intermittent issues

Monitor Power Supply Voltages

Check MOD → Diagnosis → TNC → Power Supply and verify all voltage rails are within specification (±5% tolerance).

Log voltage readings over time to identify intermittent power issues

Review Event Log for Power Events

Access MOD → Diagnosis → TNC → Event Log and look for power-related alarms or unexpected shutdowns correlating with S-RAM corruption.

Frequent power cycling can accelerate S-RAM degradation

Verify Grounding and Power Quality

Check machine ground connections and consider power line conditioning if voltage instability is confirmed.

Use a power quality analyzer to document voltage variations during machining cycles

Perform Extended Memory Test

Execute comprehensive S-RAM test via MOD → Diagnosis → TNC → Extended Memory Test to identify failing memory locations.

Run test multiple times as memory failures can be intermittent

Document Memory Error Patterns

Record specific memory addresses showing errors to determine if failures are localized or widespread.

Widespread memory failures indicate imminent S-RAM module replacement needed

Plan S-RAM Module Replacement

Contact Heidenhain service for S-RAM module replacement if hardware degradation is confirmed through testing.

Backup all machine parameters and programs before S-RAM replacement