LogrobotLM — AI fault diagnosis for ABB · KUKA · FANUC robots. It reads your robot backup in your browser (never uploaded) and pinpoints the fault. Try it free → · Le diagnostic IA qui lit la sauvegarde de votre robot, sans rien téléverser.

FANUC Alarm SRVO-038SERVO Pulse mismatch (G:%d A:%d)

FANUC SRVO-038 (“SERVO Pulse mismatch (G:%d A:%d)”): A pulse count detected when the controller was turned off differs from that detected when the controller was turned on. First check: First perform an APC reset and remaster the robot: 1. Likely part: Pulsecoder (Pulsecoder (motor encoder)).

Updated 2026-08-29 · LogrobotLM reference

Description

A pulse count detected when the controller was turned off differs from that detected when the controller was turned on. This alarm is asserted after exchange of the pulse coder or battery for backup of the pulse coder data, or loading backup data to the main board.

Remedy · Remède

First perform an APC reset and remaster the robot: 1. Press MENUS. 2. Select SYSTEM. 3. Press F1, [TYPE]. 4. Select MASTER/CAL. 5. Press F3, [RES-PCA]. 6. Press RESET. 7. Perform a Cold start. WARNING: By completing the next step you will be altering the positional reference for the robot since you are replacing hardware. You must slowly verify all positional data and touch-up any paths or points that have changed. Otherwise, you could injure personnel or damage equipment. 8. Remaster the robot if needed. If remastering is performed, you must verify all of your robot paths to prevent damage to equipment. If the pulse mismatch is not reset: 1. Check the pulse coder cable from the motor. 2. Check the internal cable set next. 3. Check the P1 cable from the robot to the controller, verify that there are no pins damaged at the robot base connection and that there is not damage to the cable. 4. Replace the pulse coder and remaster as stated in the APC RESET procedure above.

Part to check / replace · Pièce à contrôler / remplacer

FANUC SRVO-038 points to the hardware below — start here before ordering. · SRVO-038 met en cause l'organe ci-dessous : commencez par là.

Tap a part for every code that points to it — and verify the exact variant for your controller before ordering. · Touchez une pièce pour tous les codes qui la citent ; vérifiez la variante exacte avant commande.

Frequently asked · Questions fréquentes

What does FANUC alarm SRVO-038 mean?
FANUC SRVO-038 (“SERVO Pulse mismatch (G:%d A:%d)”): A pulse count detected when the controller was turned off differs from that detected when the controller was turned on. This alarm is asserted after exchange of the pulse coder or battery for backup of the pulse coder data, or loading backup data to the main board.
How do you troubleshoot FANUC alarm SRVO-038?
First perform an APC reset and remaster the robot: 1. Press MENUS. 2. Select SYSTEM. 3. Press F1, [TYPE]. 4. Select MASTER/CAL. 5. Press F3, [RES-PCA]. 6. Press RESET. 7. Perform a Cold start. WARNING: By completing the next step you will be altering the positional reference for the robot since you are replacing…
Which part is involved in FANUC SRVO-038?
SRVO-038 points to Pulsecoder (Pulsecoder (motor encoder)). Confirm the real cause against the robot backup before replacing a part.

Related codes / Codes liés

Same hardware involved / Même matériel en cause

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. · Informations indicatives issues du terrain — le manuel du constructeur et ses procédures de sécurité font foi. Ne shuntez jamais un organe de sécurité ; consignez (LOTO) avant toute intervention physique. How this reference is built →