Honeywell Experion PKS User Manual page 261

Diagnostic Check Ensure that the Device Index switches on the IOTA were not intentionally set to zero to initiate a
Device Index/IP Address reset.
Cause 1 Device Index switches set to zero.
Solution Change Device Index switches to correct setting.
Cause 2 The module is defective.
Solution Replace the module.
If Device Index switch setting matches Device Index number in 4-character display upon PGM power
up, the removed module is defective. Otherwise, go to Cause 3.
Cause 3 The IOTA is defective.
Solution Replace the IOTA.
If Device Index switch setting matches Device Index number in 4-character display upon PGM power
up, the removed IOTA is defective.
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