912
OPEN SCR FAULT
Otis · DSD 412 Elevator System
What does 912 mean?
One of the SCRs does not conduct current as expected. This condition is checked only upon request through the PCU #998 Diagnostics CDU function. The optional handheld PCDU can identify which specific SCR pair is faulty. This fault requires a DSD Power Down.
Common Causes
- Non-conducting SCR.
- Faulty SCR gating leads.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Use the PCU #998 Diagnostics CDU function to identify the non-conducting SCR pair.
- 2
Check for faulty SCR gating leads.
- 3
Replace the faulty SCR.
Verified technical data. Last updated: March 2026
Related Faults
Source: Otis DSD 412 Elevator System