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Having your windshield wipers suddenly stop working can be annoying at best and downright dangerous at worst, especially if you’re caught in inclement weather with no visibility. When your wipers aren’t working properly to clear rain, snow or debris from your windshield, it prevents you from having a safe driving experience with a clear view of the road. There are several potential causes why your windshield wipers may stop functioning – ranging from simple fixes to more complicated electrical issues. Read on to learn the common reasons windshield wipers can fail, as well as troubleshooting tips to get them working again.
Failing or Faulty Wiper Motor
One of the most common reasons your windshield wipers stop functioning is a failing or faulty wiper motor. The wiper motor is the electrical component that powers and controls the windshield wiper movement across your windshield. A bad wiper motor that is failing or broken can cause the wipers to stop working entirely. Some signs of a bad wiper motor include:
- The wipers stop working entirely in the middle of operation
- The wipers only work on one intermittent setting
- The wipers move slower than normal across the windshield
- You hear loud grinding, clicking or squeaking noises from the wiper motor
If you suspect you have a bad wiper motor, try turning your wipers on and listening from inside the vehicle to hear if the motor is running. If you don’t hear the motor running at all, it could be burned out. Other times a faulty wiper motor can still run but not have enough torque or speed to move the wiper arms.
Replacing a bad windshield wiper motor is the most reliable fix, although the replacement cost can run over $100-200 for parts and labor. On some vehicles, the wiper motors fail frequently so it may be worth investing in a higher-quality replacement unit.
Before assuming you need a costly replacement of the wiper motor, check to see if a simple fuse related to the windshield wiper circuit has blown. There is often a separate fuse just for the windshield wiper motor. A blown fuse that cuts power to the wipers is very common after vehicles encounter high current spikes or overload conditions.
Identifying which fuse powers the wipers can be tricky. Start by checking the fuse diagram on the fuse box cover or looking in your vehicle repair manual. The windshield wiper fuse may be labeled as “Wiper”, “Front Wipe” or something similar. Or locate the fuse that matches the voltage/amp rating specified in the manual. Pull out the fuse with the fuse puller and examine if the thin metal strip inside the fuse appears burnt or broken. If so, swap in a replacement fuse of the same voltage rating. If the new fuse also quickly blows, it points to an electrical issue or short that needs diagnosis by a professional.
Seized Wiper Linkage
The mechanical linkage along the undercarriage that connects the pivot points of the wiper arms can also seize up and cause wiper issues. The linkage joins together the driver and passenger side wipers so they move in unison. Over time contaminants, rust and wear inside the linkage can cause the joint to lock up. When the linkage seizes, it prevents the wiper arms from being able to sweep and arc across the length of the windshield properly.
Signs of a seized wiper linkage include:
- Only one wiper blade moves across the windshield but the other stays still
- The wiper arms move slower than normal and not the full range
- Squeaking or grinding noises coming from under the windshield cowling
To confirm a seized linkage, you’ll need to remove the plastic cowling cover underneath the windshield wipers. Then have someone run the wipers while you observe if both pivot joints move freely. Applying penetrating lubricant or freeing up the stuck pivot nuts may get the linkage moving again temporarily but replacement is best. The wiper linkage assembly connects to both wiper arms and will come as a complete repair kit.
Issues with Wiper Arms
Problems with the windshield wiper arms themselves can also lead to wiping malfunctions. The wiper arms have to apply the correct pressure to keep the rubber wiper blades firmly planted against the glass windshield. If the spring tension is off or arms come loose at the pivot points, it can affect operation.
Some common wiper arm issues that could make them stop working include:
- Broken pivot ball joints – Where the wiper arms connect to the pivot shafts underneath can work loose over bumpy roads. Then the arms flop around inefficiently instead of wiping.
- Bent or damaged arms – Accidentally closing a hood on the wiper arms can bend the sheet metal. Hitting ice buildup causes damage too. Any arm damage hinders smooth arc motion.
- Worn out tension springs – Inside the wiper arms are tiny torsion springs designed to keep blade pressure consistent. Weak spring tension lets blades skip and chatter.
In most cases, replacing old or faulty windshield wiper arms restores proper wiper function. But trying to bend arms back or DIY repairs often lead to continued problems. New replacement arms realign the pivot points and restore correct spring tension too.
Malfunctioning Wiper Transmission Mechanism
The geared transmission underneath cowling powers the sweeping motion of windshield wipers. It takes the rotary power from the wiper motor and converts it into the back-and-forth movement. Issues inside the wiper transmission prevent the smooth transition of wiping across the windshield.
Symptoms of transmission problems include:
- Loud clicking noises coming from underneath the cowling
- Wiper arms that hesitate or skip during travel
- Wipers not parking properly in the rest position
- Only certain wiper speeds malfunction but not all
The difficulty lies in determining whether the gearbox components have worn out or if small loose parts have broken inside. Dirt and hardened grease can also clog up internal components. Professionals have to disassemble and inspect the wiper transmission gears for any damaged teeth, bushings, or linkages. Replacement of the entire wiper transmission assembly may be needed if internal parts are worn out or damaged.
Frozen or Iced-Over Wiper Blades
In very cold wintery climates, frozen precipitation getting stuck to the windshield is common. During snow storms or icy conditions, layers of ice can totally encase wiper blades and prevent them from moving. Trying to force frozen wipers to scrape across the windshield can burn out the wiper motor too. The extra load strains the electrical components.
To thaw frozen wipers use these winterizing tips:
- Cover windshield with a sun shade or light tarp to allow ice to melt off.
- Pour warm, nearly hot water slowly along the base of the windshield. Avoid pouring directly onto the glass due to temperature differences cracking the windshield.
- Spray windshield de-icing fluid formulated to melt snow and ice fast without freezing further. Check that washer fluid reservoir is filled with this instead of plain water.
- Let vehicle idle with the defroster fan on high heat blowing towards the base of the windshield.
Taking preventative steps to cover windshields and keep wipers clean after snow storms minimizes problems. Installing winter wiper blades using heavier-duty rubber helps withstand freezing rain better as well.
Issues with Electrical Wiring or Connections
Like any electrical component on a vehicle, deteriorated wiring feeding power to the windshield wiper motor can cause operating issues. Fraying insulation, moisture in connectors, or loose wiring can all lead to voltage drops or electrical shorts. If the amount of power getting to the wiper motor fluctuates too much, the wipers may hesitate while moving or cut out altogether.
Inspect wiring visually first for any rubbed through spots, burnt connectors, or broken wires near moving components. Then use a multimeter to backprobe and verify battery voltage is constant while the wipers run. Damaged wires or bad grounds will show abnormally high resistance readings during diagnosis. Finally, using wiring schematics to trace circuits helps zone in on problem junctions or connectors causing drops in power. Rewiring repairs require meticulously sealing out moisture that may re-enter later.
On some vehicles, faulty relays or control modules connected inline with wiper wiring also cause failure. Testing electrical continuity through these electrical components pinpoints if replacement is needed. Intermittent contact failure inside relays and modules accounts for “sometimes” working wipers too. Vibration takes its toll over tens of thousands of wiping cycles.
Windshield Wiper Motor Noise or No Noise
An abnormally noisy windshield wiper motor points to internal damage beginning. As bearing seals wear out or armatures start to fail, extra friction produces audible bearing noise or grinding sounds. However a wiper motor that doesn’t make any humming noise could indicate it burned out.
Use a mechanics stethoscope or long screwdriver as an improvised tool to isolate exactly where noise emanates from. Place the metal rod end against the running wiper motor housing. Place your ear on the handle end to amplify noise. This guides your diagnosis better than trying to pinpoint noise by ear. Bearing roughness detected early enough can allow for bearing replacements before total unit failure.
Issues with Windshield Wiper Fluid
You expect activating the windshield washer fluid spray to accompany every few wiper strokes clearing debris away. But occasionally spray nozzles clog up or reservoir pumps fail causing loss of this function. Troubleshooting washer fluid systems only takes a few quick checks. Ensure the fluid reservoir is full first and hasn’t leaked out from a loose cap or cracked reservoir. Then listen for the fluid transfer pump activating when you engage the windshield spray controls. No pumping noise indicates a bad fluid pump that no longer transfers liquid.
Inspect the misting spray nozzles for any debris cleared out with a thin wire. If nozzles remain clogged, replace them as a set for uniform spray pattern. Adjust position of nozzles that may have bent too far off center. Finally, inspect all plastic supply tubes underneath the hood for cracks that would prevent fluid reaching spray heads. Any damaged tubes also let additional air enter the supply causing spray pump cavitation and failure. Complete hose kits with preformed shapes simplify this repair task.
Damaged Windshield Wiper Blades
Rubber wiper blades naturally wear out over time from exposure to sun, rain, snow, and debris. As the rubber loses pliability, blades no longer conform evenly across curved windshield glass. Streaks and chatter start to appear as you drive due to uneven wiping pressure on a spotty worn edge. Also properties in washer fluid, tree sap, and car wax buildup deteriorate wiper rubber.
Lift wiper arms off the windshield to visually inspect blades every few months. Look for any hardened, cracked sections along the blade. Blanching damage from the sun turns black shades to light gray indicating material erosion too. If more than 25% of the blade length appears damaged, replacement is needed. Use the wiper manufacturers size guide based on model and year of car when buying new beam style or traditional bracket wipers. Install fresh blades at least once per year before winter or rainy seasons for optimal visibility.
Diagnosing what keeps your windshield wipers from effectively clearing vision-obscuring precipitation or road spray is frustrating. But methodically checking fuses, electrical wiring, motors, mechanical joints, blades, and washer systems allows you to pinpoint root causes accurately. Consider the variety of components involved that have to seamlessly coordinate for proper wiping function. Then tackle repairs starting with more affordable items first before replacing entire expensive wiper assemblies. Maintaining fresh washer fluid and wiper blades minimizes the chances of getting caught without visibility in poor weather too. Being proactive prevents finding yourself stranded with no working wipers when you need them most.
FAQs Related to Windshield Wipers Not Working
Why won’t my windshield wipers turn on?
The most common reasons your windshield wipers won’t activate at all include electrical problems like a faulty wiper switch, failed wiper relay, bad wiper motor, blown fuse, or severed wiring. Mechanical causes include a seized wiper linkage, stripped gears, or jammed transmission preventing arm movement even if the motor runs.
Why do my windshield wipers stop in the middle while wiping?
When windshield wipers stop mid-wipe suddenly, it often indicates an overheating, overloaded or worn out wiper motor drawing excessive current. Thermal cut-off switches inside the unit then trip to protect from immediate failure. It also happens due to low voltage from a weak car battery or alternator not supplying consistent power during operation.
Why are my windshield wipers moving slower than normal?
Slow moving windshield wipers point to low fluid reaching the wiper motor, worn out pivot bushings, misaligned arms, or a failing wiper motor low on torque. Binding inside the wiper transmission prevents full travel speed too. Any lack of lubrication along the moving mechanisms also increases friction and drag during sweeping.
Why is only one windshield wiper working but not the other?
When one wiper works but the other doesn’t, start inspecting tie rods and mechanical linkage connecting the two arms underneath the cowling. Seized joints or broken rods allow one side to operate independently while the linkage prevents symmetrical movement on both sides.
How do I fix chattering or squeaking windshield wipers?
Chattering wiper blades or noisy operation stems from loss of uniform pressure holding the edge securely on the glass. Replace worn, rigid blades immediately and ensure the pivot joints don’t leak allowing sagging. Also clean any sticky buildup with isopropyl alcohol and reapply rubber rejuvenator spray to maintain supple blade edges.