FANUC Alarm SRVO-138 — SERVO SDAL alarm
Manufacturer wording — SERVO SDAL alarm (G:%d A:%d)
The manual prints placeholders; your controller fills them in with the real group, axis or number.
FANUC SRVO-138 (“SERVO SDAL alarm”): The feedback data from pulse coder was abnormal by: 1. First check: 1. If the alarm disappeared by power off/on, please make sure the cable shields are properly grounded. Likely part: Pulsecoder (Pulsecoder (motor encoder)).
Updated 2026-09-17 · LogrobotLM reference
Description
The feedback data from pulse coder was abnormal by: 1. Noise on the pulse coder. 2. The interpolation circuits of the pulse coder are broken.
Remedy
1. If the alarm disappeared by power off/on, please make sure the cable shields are properly grounded. 2. If this problem occurs repeatedly, replace the pulse coder and master the robot..
Part to check / replace
FANUC SRVO-138 points to the hardware below — start here before ordering.
Tap a part for every code that points to it — and verify the exact variant for your controller before ordering.
Related codes
Same hardware involved
Indicative field information — the robot manufacturer's manual and safety procedures always prevail. Never bypass a safety device; apply lockout/tagout (LOTO) before any physical intervention. How this reference is built →