What the SRVO-135 alarm means

A cooling fan inside the servo amplifier has stopped or is running below speed. This fault ranks high in our FANUC R-30iA / R-30iB / R-30iB Plus service records, and the first site inspection usually finds the source.

Most common causes

  • Fan failed (bearing wear - consumable item)
  • Fan connector loose
  • Fan power supply fault in the amplifier
Field note: The first cause shows up most on real machines, so verify it before you go further.

Step-by-step field fix

  1. Replace the amplifier cooling fan - cheap part, do it promptly
  2. Clean dust from heatsinks while the unit is open
  3. Do not run long with a failed fan: overheating cascades into IPM/amp damage
Safety first: For FANUC srvo-135, amplifiers and boards are live parts: hot-plugging a board burns interface circuits, and body static can kill sensitive devices. On site you may look at after confirming power-off the first step yourself: Replace the amplifier cooling fan - cheap part, do it promptly. Beyond that it is live boards and power devices work - leave it to a professional.

How we diagnose amplifier/hardware alarms on site

FANUC srvo-135 belongs to the amplifier & hardware family. On FANUC srvo-135 the failing stage is alpha-i / beta-i servo amplifiers with PSM supply modules and SVM servo modules (SPM where spindles fit) on the R-30iB Plus / R-30iB Mate Plus / R-30iA - the amplifier and drive hardware itself plus its periphery: boards, fuses, cooling, supply, connectors and self-test. We start reading FANUC srvo-135 at the iPendant ALARM screen (SRVO / MOTN / SYST / INTF prefixes) together with the amplifier's 7-segment status code.

The chain involved in FANUC srvo-135 runs: control-side signal -> amplifier board (drive and sense circuits) -> fuses and supply -> cooling -> motor-side output.

When FANUC srvo-135 fires, clear the external causes first - Many hardware alarms are not hardware at all but external conditions: a packed filter causing over-temperature, a missing phase causing undervoltage, a loose connector causing a communication drop. Our order clears the externals first - clean, replace the mat, measure supply, re-seat terminals - near-zero cost and a high hit rate. Only when externals are gone do we judge boards or power stage. It also keeps the quotation honest: we do not sell parts we have not earned.

Field notes on this page cover FANUC srvo-135 (FSAL - Fan Stop Alarm); written by the Henghuan repair team, updated 2026-10-01.

No luck? Hand it to the team that fixes this daily

Tell us these three: alarm code, robot model, and the operating condition at the alarm. FANUC srvo-135 FANUC srvo-135 is a diagnosis our engineers do daily, and phone/video remote diagnosis is free.

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Related Amplifier & Hardware alarms

SRVO-057 — FSSB Disconnect SRVO-068 — DTERR - Data Transmission Error SRVO-069 — CRCERR - CRC Error SRVO-071 — SPHAL - Soft Phase Alarm SRVO-072 — PMAL - Pulse Coder Phase Alarm SRVO-073 — CMAL - Pulse Coder Count Error
Same family: this code belongs to the Amplifier & hardware alarms family - the page collects all Amplifier & hardware-family codes we have handled, with the common inspection order and spares.
Other brands: see our KUKA, ABB, Yaskawa and Universal Robots field-fix libraries — or the full 10-brand hub.

Frequently asked questions

QWhat does the FANUC srvo-135 alarm mean?

A cooling fan inside the servo amplifier has stopped or is running below speed. This fault ranks high in our FANUC R-30iA / R-30iB / R-30iB Plus service records, and the first site inspection usually finds the source. FANUC srvo-135 sits in the amplifier & hardware family; on our work orders the highest-frequency trigger for this code is "Fan failed (bearing wear - consumable item)".

QCan I clear a FANUC srvo-135 alarm myself?

Whether FANUC srvo-135 clears on its own depends on the outcome of "Replace the amplifier cooling fan - cheap part, do it promptly". Finish the flow with "Do not run long with a failed fan: overheating cascades into IPM/amp damage" to confirm FANUC srvo-135 - do not skip it. If that step is clean, the second most frequent cause on FANUC srvo-135 is "Fan connector loose". After clearing FANUC srvo-135, watch it for one shift. A second trip means stop and let an engineer arrive with the right test gear for live boards and power devices.

QFor hardware alarms like FANUC srvo-135, does it always mean an expensive part swap?

The commonest causes we see on FANUC srvo-135 are "Fan failed (bearing wear - consumable item), Fan connector loose, Fan power supply fault in the amplifier", so we stock the van against those. For FANUC srvo-135 specifically, we carry fuses, filter mats, common connectors and terminals; boards are stocked by type or go through the repair channel. For FANUC srvo-135, on hardware alarms we inspect before quoting - we do not open with replace the power stage. Before we roll, tell us what FANUC srvo-135 shows on the iPendant ALARM screen (SRVO / MOTN / SYST / INTF prefixes) together with the amplifier's 7-segment status code and what the machine was doing - phone or video triage is free.

This page on FANUC srvo-135 was written by the Henghuan Robotics repair team from field service experience. Alarm descriptions are our own summary for troubleshooting reference and may vary by controller and software version — when in doubt, check your FANUC documentation or contact us. Henghuan is an independent service provider, not affiliated with or endorsed by FANUC.