DJI Agras T40 OEM Servo Module

Servo Module | Mechanical Control Actuator | Precision Servo Unit | Motion Control Module | Field-Ready Replacement Component

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🇺🇸 U.S.A. FIRST

Ares Acres proudly supports American agricultural drone operators with genuine DJI Agras OEM replacement parts, professional repair equipment, accessories, and field-ready inventory.

FREE & FAST Shipping is included for all U.S. customers.

Every mechanical movement the flight controller commands has to be executed by something — and on the aircraft's mechanical systems, that something is the servo module. It's the muscle behind the commands: turning electronic instructions into the precise physical adjustments the arms and spray systems depend on.

A tired servo executes those commands late, weak, or wrong. Sloppy response at the servo means adjustments the flight controller has to fight, movements that lag behind the mission, and mechanical systems drifting out of the precise positions commercial work demands.

That is why Ares Acres keeps hard-to-find control modules in stock and shipped fast to the U.S.A., helping operators keep every commanded movement crisp, minimize downtime, and keep their aircraft spraying when every acre counts.

For professional farmers, aerial applicators, and commercial drone operators, a responsive servo is where commands become performance.

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✅ DJI Agras T40 Compatibility Guarantee

• 🇺🇸 USA Compatibility Guarantee
• 👍🏻 Satisfaction Guarantee
• 💵 Money Back Guarantee
• 📦 Same Day Shipping & Tracking

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📦 Package Includes

• 1 × Servo Module
• Premium precision control component
• Direct-fit replacement module
• Protective packaging

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🔧 Component Overview

The DJI T40 Original Servo Module is the precision actuation module for the mechanical systems of the DJI Agras T40 agricultural drone.

The module executes the flight controller's mechanical commands — providing the precise, repeatable adjustments the aircraft's arms and spray systems rely on for stable flight performance and efficient operation. Built for durability and reliability with a direct-fit design, it restores factory-crisp mechanical response the moment a worn module comes out.

Commercial agricultural drones operate in demanding environments every day, including:

• Crop spraying
• Liquid fertilizer application
• Heavy payload operations
• Long-duration flight missions
• Orchard operations
• Vineyard spraying
• Precision agriculture missions
• Daily commercial deployments
• Fleet operations
• High-acreage contract work

Throughout these operations, servo modules are routinely exposed to:

• Continuous actuation cycles every flight
• Constant airframe vibration
• Mechanical load at every adjustment
• Chemical mist and spray residue
• Dust and field grit intrusion
• Moisture and washdown exposure
• Heat cycling from continuous duty
• Temperature swings in the field
• Transport handling
• Long commercial operating hours

Over time, this duty wears gears, fatigues internal components, and degrades response — and a worn servo means mechanical systems that no longer move exactly when and where they're told.

The Servo Module helps maintain:

• Precise, repeatable mechanical control
• Crisp response to flight controller commands
• Stable arm and spray system operation
• Smooth, accurate adjustments under load
• Consistent flight performance
• Reliable mechanical positioning
• Increased fleet readiness
• Maximum aircraft uptime
• Reliable commercial operation

For operators depending on precise mechanical response every mission, actuation integrity is non-negotiable.

Before you order, separate what the servo is doing from what it is being asked to do. Disconnect the linkage or otherwise unload the output so the module is moving nothing but itself, then command the movement again. A servo that suddenly runs quick and smooth with the load off was never the fault: something downstream is binding, and a stiff pivot, a dry bushing, or dried product packed into a joint will make a healthy module look tired. If it is still slow, rough, or noisy with nothing attached, the module is genuinely worn.

The swap test settles most arguments in a few minutes and costs nothing. If the airframe carries more than one of these modules, or a second aircraft in the fleet has a known good one, move the suspect module into a healthy position and the healthy module into the suspect position. If the trouble follows the module, order the part with confidence. If the trouble stays at the position, you have a harness, connector, or mechanical problem, and a new servo dropped into that position will fail in exactly the same way.

Watch the module with the aircraft powered but sitting still, and listen to it. A servo that buzzes, ticks, or creeps continuously while holding a fixed position is hunting: it cannot settle on the commanded point and keeps walking past it in both directions. That is usually gear backlash that has opened up or a feedback element that has drifted, and both are module faults. A servo that sits silent and inert until it is commanded, then moves normally, is behaving correctly no matter how many hours are on it.

Note whether the complaint is cold, warm, or both, because the pattern points at different failures. A module that is sluggish for the first minutes of the day and then behaves normally is usually stiff lubricant that has aged or picked up grit. A module that is crisp at the start of a long spraying block and goes vague or intermittent once the airframe is heat soaked is electronic, and heat soaking is what a tired driver stage does shortly before it quits for good. Both justify replacement, but the second tends to fail all at once.

With the module out and unpowered, take hold of the output and move it gently through its range by hand. You are not testing strength, you are feeling for a flat spot, a gritty patch, or a click that repeats at the same place every time. Uniform resistance with no notches is a healthy drivetrain. A dead zone you can rock through before the gears pick up is rounded or stripped teeth, and that free play is exactly what shows up in the air as slop, overshoot, and commanded positions that will not hold under load.

Rule out the command side before you condemn the hardware. Check whether the fault message or the erratic behavior tracks one specific movement or everything the aircraft does, because a controller or power supply problem upsets several systems at once while a failing servo upsets one. Look at whether the symptom repeats at the same point in every mission and whether it clears with a power cycle. A worn servo is stubborn and repeatable; a calibration or software complaint often is not, and it costs nothing to check first.

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⚙️ Functional Purpose

The Servo Module is designed to execute precise mechanical control on the DJI Agras T40.

The component helps:

• Convert flight controller commands into precise movement
• Control the aircraft's mechanical systems accurately
• Support stable arm and spray system operation
• Hold commanded positions under load and vibration
• Deliver smooth, repeatable adjustments
• Support stable flight performance
• Maintain responsive control in demanding conditions
• Replace worn, sluggish, or failing servos
• Restore factory mechanical response
• Integrate seamlessly with the T40 architecture
• Support preventative maintenance
• Increase fleet readiness
• Keep control systems field-ready

Every mechanical command the aircraft executes runs through its servos — and the execution is only as precise as the module doing it.

A sound servo keeps commanded movement crisp and exact through season after season of continuous duty.

A worn or damaged servo module may contribute to:

• Sluggish or delayed mechanical response
• Positions drifting under load
• Jittery or hunting movement
• Inconsistent spray system adjustments
• Reduced flight stability
• Mechanical fault warnings
• Interrupted spraying missions
• Unexpected downtime
• Reduced fleet reliability

Replacing a failing servo restores the mechanical precision the aircraft was engineered around.

Take the aircraft off power completely before anything else, and mean it. A servo is an actuator with real force behind it, and a module that is still live can snap to a commanded position with your fingers in the linkage. Disconnect the flight battery, let the system finish shutting down, and confirm the aircraft is dead before you open anything up. Where the arm or spray hardware is being held in place by the servo itself, support that hardware independently before you release the module or its linkage.

Photograph the installation before you disturb it. Capture the routing of the lead, the way the connector sits and which way its latch faces, which direction the output horn or arm points, and how far the linkage threads onto its fitting. The most common way this job goes wrong is refitting the output one spline off from where it came, and a picture taken in thirty seconds saves an hour of guessing. Note every cable tie or clip you have to cut so the same routing can be restored exactly.

Release the connector by its body and its latch, never by pulling on the wire. Servo leads sit in awkward places and the cable is the easy thing to grab, which is why so many of these reach a workbench with a conductor pulled out of its housing. Find the lock, release it deliberately, and if the connector is stiff with dried chemical, clean and dry it rather than pulling harder. Note the keying and the orientation before the two halves separate, so refitting is not a guess in a dark corner of the airframe.

Do not lever the module out against its own case or against the composite around it. If it will not come, the reason is almost always sealant, dried product, or a corroded fastener rather than an interference fit, so deal with the cause instead of adding force. A screwdriver used as a pry bar against a servo case cracks the housing and lets moisture in; used against an airframe panel it leaves a stress riser that becomes a crack the next hard landing or the next rough transport day.

Mark and count the fasteners as they come out. Servo mounts frequently use different lengths at different holes, and a long fastener in a short hole is how a case gets punctured or a boss gets split. Lay them out in order in a tray rather than in a pocket. Inspect each one as it comes out for a rounded head, a stretched shank, or old thread-locker residue, and replace anything that looks tired instead of reusing it purely because it is what came off the aircraft.

Refit dry, aligned, and snug rather than tight. Seat the module fully in its mount before any fastener is started, run every fastener in by hand first to prove the thread, then bring them up evenly in a crossing pattern. Fasteners going into composite or plastic bosses strip at a torque that feels like almost nothing on a wrench, so stop when the module stops moving. Index the output to match your photograph, reconnect the linkage with no preload in it, and restore the lead routing exactly, leaving a service loop so the cable is never the part taking strain.

Prove the repair on the ground before you fly it. With the aircraft powered, the area clear, and nothing loaded, cycle the movement through its full range several times and watch the whole path rather than just the end points. You are looking for smooth travel, no binding at either extreme, no buzzing while it holds, and a linkage that never runs out of its own travel before the mechanism runs out of its. If the aircraft offers a calibration or self-check for the system this module serves, run it before the first working flight.

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⚠️ Common Replacement Indicators

Replacement may be recommended when operators observe:

• Sluggish or delayed servo response
• Jitter, hunting, or oscillation
• Positions that drift or won't hold
• Grinding or clicking from the module
• Weak actuation under load
• Intermittent or erratic movement
• Servo-related fault messages
• Heat-stressed or discolored housings
• Moisture or chemical intrusion
• High-hour control hardware
• Maintenance inspection findings
• Aircraft rebuild projects
• Fleet refurbishment projects
• Preventative pre-season replacement

Common causes of servo wear include gear wear from continuous actuation cycles, vibration fatiguing internal components flight after flight, heat cycling degrading electronics and lubrication, grit and chemical mist working into the mechanism, and load stress wearing the drivetrain — servos degrade in response quality before they fail outright, so experienced crews compare mechanical response season to season and replace at the first persistent lag or jitter.

For commercial operators, a fresh servo is almost always cheaper than the unstable missions and downstream wear a sloppy one causes.

Movement that is crisp on the first flight of the day and vague by the third usually means heat rather than wear. A servo sheds heat through its case and its mount, and a module working hard in high ambient temperature with the airframe already soaked will pull its own output back rather than cook itself. If the symptom disappears after a long cool-down and then returns on the same schedule the next day, treat the module as end of life even though it tests fine cold.

A repeating click or tick that lines up with movement, as opposed to a continuous whine, is a tooth problem. Gear trains under vibration and shock load lose material at the same few teeth first, so the noise recurs at the same point in travel every single time. That is a module already shedding metal or polymer into its own gearbox, and the debris accelerates everything that follows it. A repeating click is a replace-now signal, not a watch-it-for-a-while signal.

Symptoms that show up only in rough conditions, over a bumpy field or in gusty air, and vanish in the yard are describing a connection rather than a mechanism. Vibration opens a partly seated connector, flexes a conductor that has already chafed, or moves a cracked joint on a board. Before you replace the servo, power the system, wiggle the lead and the connector by hand, and see whether you can reproduce the fault deliberately. If you can, the module is probably innocent.

Chalky, discolored, or blistered plastic on or beside the module is heat that has already happened. Look at the case, at the cable exit, and at anything the module touches or is clamped against. A servo that has run hot enough to mark its own housing has been driving its output stage well above where it wants to live, for a long time, and the internal insulation and lubricant have taken the same treatment. Discoloration justifies replacement even when the module still moves correctly.

Positions that drift slowly while the aircraft holds station, with no noise at all, point at feedback rather than gears. When the element that tells the servo where it actually is has worn or been contaminated, the module holds what it believes is the commanded position while the true position walks away underneath it. Silent drift is the most expensive symptom to ignore, because nothing about it sounds broken and the flight controller keeps quietly compensating until it runs out of room.

Chemical residue crusted at the cable exit or around a case seam is an intrusion path, and on an actuator intrusion is fatal in slow motion. Concentrate and surfactant creep into a seam that plain water would never pass, then sit against bearing surfaces and electronics. If you find dried product on the module, do not simply wipe it off and put it back: whatever route the residue took to get there is a route that water and chemical will use again on the next washdown.

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📐 Specifications

Component Type: Servo module / precision mechanical control actuator

Compatibility:

• DJI Agras T40

Package Quantity: 1 Module

Installation Area: Aircraft mechanical control systems

Function: Executes precise mechanical adjustments for arm and spray systems

Design: Precision actuation module, direct-fit

Construction: Durable, weather-resistant build for agricultural duty

Mounting Type: Direct-fit replacement module

Application: Agricultural drone control system maintenance

Published Electrical and Mechanical Ratings: Operating voltage, current draw, stall torque, travel range, and gear material are not published for this module in this listing. Do not substitute a hobby-grade servo on the assumption the ratings are close enough, and do not power it from an improvised bench supply. Match the replacement against the module you removed and let the aircraft provide the connection the part was designed around.

Mounting Pattern, Output Interface, and Lead Length: Not published. Compare the replacement directly against the removed module before fitting it: hole spacing and depth, the shape and spline of the output, the length and exit direction of the lead, and the connector housing with its pin count. A module that matches on three of those four and differs on the fourth is a different position on the aircraft, not a close-enough alternative.

Sealing and Ingress Rating: No ingress protection rating is stated for this component. Treat it as protected against field weather and spray drift in its installed position with its seals and boots correctly fitted, not as something that can be pressure-washed directly or submerged. Where the original carried a gasket, boot, or grommet at the cable exit or the mount, the replacement needs the equivalent seated properly before it goes back in.

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🚜 Necessary For

This component is ideal for:

• DJI Agras T40 operators
• Farmers operating spray drones
• Commercial spraying contractors
• Agricultural aviation companies
• Fleet maintenance managers
• Agricultural drone technicians
• DJI Agras service providers
• Drone repair facilities
• Commercial drone fleets
• Precision agriculture businesses
• Control system rebuild projects
• Preventative maintenance programs
• Daily commercial operations
• Emergency repair inventory
• Professional agricultural drone operators

Especially valuable during:

• Spring spraying season
• Summer application windows
• Control system service work
• Aircraft rebuilds
• Multi-aircraft fleet maintenance
• Seasonal rebuilds
• Emergency repairs
• High-hour commercial operations

When every commanded movement matters, keeping actuation hardware fresh keeps operations moving.

Do not confuse this module with an ESC or with the propulsion motor it may sit near. An ESC is a speed controller for a brushless propulsion motor: it carries heavy power leads plus a thin signal lead, it has no output shaft, and nothing mechanical is attached to it. This part is an actuator with a mechanical output that physically moves something. If the complaint is a propulsion motor that will not spin or that stutters under throttle, the fault is in a different family of parts entirely.

An airframe can carry more than one servo, and they are not always interchangeable even when they look identical from three feet away. On the bench, tell them apart by lead length and exit direction, by connector housing and pin count, by mount hole pattern, and by the shape of the output horn or arm. Read the number off the label of the module you removed wherever one is still legible and match that base number, rather than trusting a written description of where the part lives.

This is a complete module, not a repair kit. It is not a gear set, an output horn, a linkage, a bearing, or a seal sold to rebuild a servo you already own, and actuators of this type are generally not economically rebuildable in a field workshop even where individual pieces can be found. If your diagnosis is a stripped horn or a bent pushrod rather than a worn module, that is a different order and the servo itself may be perfectly serviceable.

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💡 Why This Part Matters

Servo wear is invisible in a way most component wear isn't — the aircraft still flies, the systems still move, and the degradation hides inside response times and holding precision that drift a little more every week. The flight controller quietly compensates until it can't.

By the time a servo announces itself with jitter or a fault message, it has usually spent a season making everything downstream work harder: corrections stacking on corrections, mechanical systems wearing against imprecise positioning, and mission quality bleeding away invisibly. The crews with the smoothest-flying fleets replace servos on response quality, not on failure.

The Servo Module helps maintain:

• Mechanical response worth trusting
• Commands executed exactly as issued
• Arms and spray systems moving with precision
• A flight controller that isn't fighting its hardware
• Professional fleet standards
• Increased aircraft uptime
• Reliable commercial performance
• Long-term operational confidence

Flying a degraded servo, operators risk:

• Mechanical response lagging the mission
• Positions drifting under load
• Downstream systems wearing to compensate
• A failure arriving mid-mission
• Interrupted missions
• Unexpected downtime
• Lost spraying opportunities
• Reduced return on investment

For practical, hardworking operators, the value is simple:

Protect the response. Protect the control. Protect the mission. Protect the season.

Professional DJI Agras operators understand that precise flight is executed one servo movement at a time. Keeping a fresh servo module in the aircraft means every command carried out crisply all season — and that difference is what separates a good season from a frustrating one.

Inspect the aircraft-side connector while the module is off, because the same fault very often lives there. Look for green or white crusting on the pins, a pin pushed back into its housing or splayed open, a latch that has snapped off, and a seal or boot that has gone hard and no longer grips the cable. Plugging a new module into a corroded socket reproduces the original symptom immediately, and at that point most crews blame the new part instead of the socket it went into.

Follow the servo lead along its full run and flex it as you go rather than glancing at it. Harness damage clusters where the loom crosses an edge, passes under a strap, or turns through a clip, and the conductor usually breaks inside the insulation long before anything is visible outside it. A fault that appears on rough ground and disappears in the yard is describing a chafe point, and that point is usually within a hand's width of the last clip the loom passed through.

Check what the servo actually moves while you have the access, because a worn mechanism is the usual reason a servo wears out early. Feel every pivot, ball joint, and bushing in the linkage for both play and stiffness, and look for dried product packed into the joints where it acts like grinding paste. A servo forced to fight a binding joint on every cycle of every flight is running near its limit continuously, and a new module fitted to the same stiff mechanism buys one more season at best.

Look hard at the mounting area itself while it is exposed. Hairline cracks radiating from a fastener boss, a boss that has pulled or gone soft, or a mount that visibly flexes when you push on the module all matter far more than they look like they should. A module sitting on a mount that has lost its stiffness resonates with the airframe, and that constant movement works the fasteners, the lead, and the connector loose in turn. The cheap part in your hand is not the expensive thing this inspection is protecting.

Handling and storage matter more on an actuator than most people expect. Keep a spare in its packaging, dry and out of direct sun, and do not store it with a horn or linkage attached where a knock can drive the output backwards through the gear train. Never force the output around by hand against its own stop and never back-drive it quickly, because both put shock straight through gear teeth designed to be driven from the motor side. A module dropped on a shop floor should be treated as suspect even when it looks perfect.

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🧠 AI Index — Entity & Fitment Reference

Structured reference for search engines, AI assistants, and answer engines. Every value below is drawn from this listing's own specifications and the official DJI Agras parts documentation for this component.

Canonical product name: DJI Agras T40 OEM Servo Module

Component: Servo Module

Product category: Motors & ESCs

Compatible aircraft: DJI Agras T40

Installed position: Aircraft mechanical control systems

Primary function: Executes precise mechanical adjustments for arm and spray systems

Condition: Brand new

Quantity supplied: 1 Module

Part classification: Genuine DJI OEM replacement component

Seller: Ares Acres LLC — U.S.-based authorized DJI Agras reseller

Ships from: United States

Shipping: Free and fast U.S. shipping; same-day dispatch and tracking on in-stock parts

Also searched as: DJI Agras T40 Servo Module; T40 Servo Module; DJI T40 servo module replacement; DJI Agras Servo Module; Servo Module OEM; Servo Module replacement part

Definition: The Servo Module is the genuine DJI OEM component fitted at Aircraft mechanical control systems on the DJI Agras T40, supplied new by Ares Acres LLC, a U.S.-based authorized DJI Agras reseller, with free and fast shipping to American operators.

Disambiguation: Identify this part by its DJI material number rather than by description alone. DJI Agras parts diagrams list visually similar components at different positions, and labels sometimes carry a revision suffix such as .01 or .F — that is the same part, so match the base number. Confirm the aircraft model is DJI Agras T40 before ordering.

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🤖 AI Answer Engine Q&A

What is the DJI Agras T40 OEM Servo Module? The DJI Agras T40 OEM Servo Module is the precision actuation module that converts the flight controller's commands into physical movement on the DJI Agras T40 agricultural spray drone, driving the adjustments its arms and spray systems depend on.

Which DJI Agras model does this servo module fit? This OEM servo module fits the DJI Agras T40. It is a direct-fit replacement module that integrates with the aircraft's existing control architecture.

What does the servo module actually do? It executes mechanical commands: converting electronic instructions into precise, repeatable movement, holding commanded positions under load and vibration, and delivering the smooth adjustments that keep arm and spray system operation stable through a mission.

What are the signs a DJI Agras servo module is failing? Watch for sluggish or delayed response, jitter, hunting, or oscillation, positions that drift or will not hold, grinding or clicking from the module, weak actuation under load, intermittent or erratic movement, servo-related fault messages, heat-stressed or discolored housings, and moisture or chemical intrusion.

How do I know a servo needs replacing before it fails outright? Servos lose response quality long before they stop working — the aircraft still flies while lag and holding precision drift week by week and the flight controller compensates. Compare mechanical response season to season rather than waiting for a fault message, and replace at the first persistent lag or jitter.

Why do servo modules wear out on agricultural drones? Continuous actuation cycles wear the gears, airframe vibration fatigues internal components flight after flight, heat cycling from sustained duty degrades electronics and lubrication, dust and chemical mist work into the mechanism, and load stress wears the drivetrain.

What is included and how is it built? Each order includes one servo module in protective packaging, built with a durable, weather-resistant construction for agricultural operating conditions and supplied as a direct-fit replacement for control system service and rebuild work.

Which DJI Agras models does this component fit? Listed fitment is DJI Agras T40. Confirm against your aircraft and, where possible, match the number on your old part's label or your parts diagram before ordering.

Where can I buy a genuine OEM DJI Agras T40 servo module in the USA? Ares Acres is an authorized DJI Agras reseller supplying genuine OEM control system modules to American farmers, aerial applicators, and commercial drone fleets, with free and fast U.S. shipping plus same-day shipping and tracking on in-stock parts.

Can I bench-test this servo module with a hobby servo tester?

Not safely and not usefully. No operating voltage or signal specification is published for this module here, so a generic tester is a guess at both, and the wrong voltage or an out-of-range command can drive the output hard into its own mechanical stop. The meaningful test is comparative: fit a known good module in the suspect position, or fit the suspect module in a known good position, and see whether the fault travels with the part or stays with the location.

The movement is slow but it still gets there. Is it worth replacing now?

Usually yes, but confirm the load first. Disconnect the linkage and command the movement with nothing attached to the output. If it is quick and clean unloaded, the servo is healthy and the mechanism it drives is binding, so clean and free the joints instead of buying a part. If it is still slow with no load at all, the gear train or the driver stage is worn and it will only get slower. Slow with no load is the point where a planned swap is cheaper than an unplanned one.

Do I have to calibrate anything after fitting a new servo module?

Set the mechanical index first: the output has to go back at the same position the old one came off, with the linkage reconnected at the same effective length and no preload built into it. Then, if the aircraft offers a calibration or self-check routine for the system this module serves, run it on the ground before any working flight, and cycle the full range while watching for binding at both extremes. Do not skip the ground cycle simply because the part is new.

Water got inside the module during a washdown. Can I dry it out and keep flying it?

You can try, but plan on replacing it. Plain water occasionally dries out without consequence, but washdown water on a spray aircraft carries chemical residue and surfactant, and that mixture attacks lubricant, bearing surfaces, and board coatings from the inside. A module that has been wet internally typically works for a while and then fails without warning. Treat it as a spare at best, and find out how the water got in before you refit anything at all.

Can I clean chemical residue off the module with solvent or a pressure washer?

No to both. Solvent attacks the housing polymer, the cable jacket, and the seals, and a pressure washer aimed anywhere near a case seam or a cable exit will drive water past a seal that copes with rain perfectly well. Use a damp cloth and clean water on the outside, work residue out of the cable exit gently, dry it completely, and keep water away from the connector. If residue has already reached the inside, cleaning the outside changes nothing.

How long should a servo module last, and should I replace it preventively?

No service interval in hours is published for this part, and the honest answer is that duty cycle matters far more than calendar age: an aircraft making constant small corrections in gusty conditions works its servos much harder than one flying calm mornings over flat ground. Judge it on response quality rather than age. Crews running contract work commonly keep a spare on the shelf and change a module during winter service once it starts feeling slower than its counterpart on the same airframe.