Why Do Motorcycle Headlights Blink?(Quick Fix)

Why Do Motorcycle Headlights Blink?

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Why Do Motorcycle Headlights Blink?

Motorcycle headlights increases the visibility, both during the day and at night.

The headlights typically feature LED lights that boast more durability than conventional light sources as they require less energy and last much longer.

They also offer a wider light beam, making it easier to see those in front and on the side of your motorcycle.

The blinking may be caused by the damage to the electrical system that causes the flickering and flashing lights. Damaged or frayed wiring harnesses, broken plugs, corroded battery terminals, and clogged oil filters can all be culprits. To resolve this Clean or replace the faulty wiring system and relays.

Other Possible causes:

1. Dyeing Battery

One main reason why motorcycle headlight blink is that you have over-charged the battery. Under normal circumstances, when you fully charge a battery, it will stop charging automatically.

However, if your battery charges too long and you cannot turn it off, its cells will heat up and produce gases. The gases cause the battery to emit a strange glow.

This is called thermal runaway and is, more often than not, the root cause of all motorcycle flashing.

2. Failing Alternator

If you need to fix the charging system for your motorcycle, it does not matter how long you charge the battery. The alternator will still produce a steady stream of electricity and overcharge the battery.

3. Poor Wiring

Sometimes the problem is with the wiring. For example, there is a short between the wires you use to charge your motorcycle battery.

When this occurs, you get intermittent flashes of lights or may see a solid light after every turn of the headlight switch.

4. Low Voltage

You may drain the battery because the alternator isn’t using enough power to keep it appropriately charged.

Why Do Motorcycle Headlights Blink?

The same happens if your bike is not running in cold weather and needs more run time on a single charge.

5. Charging Cable

Your charging cable may have a problem, or your bike’s battery may need to produce more electricity to charge the batteries.

That is why you need an alternator that can keep up with the charging needs of your motorcycle.

6. Faulty Headlamp Switch

Some motorcycle lights are not designed to withstand the charge voltage without a protection circuit. The protection circuit breaks down and causes the light to flash.

What Does Flashing Mean on A Motorcycle?

Flashing HeadlightsTurn one or more headlights very quickly and then shut them off; repeatedly. The lights on top of the car may also flash.
Flashing Turn SignalsSignals are ON or OFF for several seconds, then turn off.
You can do this when the motorcycle is about to make a turn.

The purpose is to let other drivers know that the rider intends to turn.
Flashing Brake LightBrake light is ON and OFF as quickly as possible and You may do this while driving slowly through heavy traffic.

To warn cars behind the motorcycle that they need to slow down or change lanes so they can pass safely.
Flashing Headlights, Brake Light, And Turn SignalsAll three lights flash rapidly for two to three seconds.
You can do this to get attention from other drivers.

You often use it in emergencies to distract the car driver from an accident.
Flashing Headlights and Turn Signals, Blinkers On And Off, Or Angel EyesAll three lights flash rapidly, then stop blinking and remain on or off for several seconds.

This occurs when the motorcycle is turning, You can do it to get attention from other drivers or to communicate with another motorcycle rider.

Why Are My Taillights Flickering?

Burnt-Out BulbsReplace your old, burnt-out taillights with new bulbs.
Shorted WiringCheck for any exposed wires or loose connections that could be shorting.
Fuses And Circuit BreakersEnsure no blown fuses or tripped circuit breakers are in those taillights’ circuits. This is a common reason lights may begin to flicker!
Stuck RelaysIf you sense a relay or a switch is stuck, turn on the hazard lights and see if they continue functioning.  If they do, unplug them and leave them off for 15 minutes.

If they don’t operate, replace any burnt fuse in their circuit.

After turning off the hazard lights, check and clean any debris from within the wiring harnesses for all affected lamps.
Loose Or Broken GroundEnsure all grounds are clean and secure. For example, your rear window may be loose, which could cause a flicker in the tail lights.

Check for corrosion on any grounded metal surfaces and remove corrosion accordingly.
Alternator Or Battery IssuesA faulty alternator or dead battery could be the culprit. Have the electrical system inspected by a professional mechanic.

Why Do Motorcycle Lights Flash and Flicker?

FactorExplanationHow to fix
Damaged BulbDamage to the electrical system can cause flickering and flashing lights.

Damaged or frayed wiring harnesses, broken plugs, corroded battery terminals, and clogged oil filters can all be culprits.
Replace the damaged wiring system, so get your hands dirty.
Faulty Wiring ConnectionFaulty, dirty, or corroded wiring systems can cause your motorcycle lights to flicker.Clean or replace the faulty wiring system and relays.
Failing Voltage RegulatorA faulty voltage regulator can cause an electrical short.

The short will cause the motorcycle lights to flash and flicker, especially if the other electrical system components are intact.
Replace the voltage regulator with a new one or replace the faulty wiring.
Failing Electrical FuseA failing fuse will cause your motorcycle lights to flicker, especially if other electrical components work fine.Replace the fuse and get your hands dirty.
Damaged Electrical ConnectionsThis one might not result from faulty wiring, but it is worth mentioning because it can cause flickering lights.

Worn or abraded contact surfaces on the connectors that make up your motorcycle’s electrical system will cause them to fail, resulting in amber flashing lights.
Repair the damaged connector or replace the entire electrical system.
Use Of Aftermarket LED LightsAftermarket LED lights are often lower in quality than OEM parts.

They may not withstand constant vibration and shock, leading to flickering lights
Replace the LED lights with OEM parts or a better, aftermarket product.

Do Motorcycle Lights Come on Automatically?

Yes! Motorcycle lights automatically come on when the bike runs and you turn on the key. If your bike’s lights are not coming on automatically, please follow these steps to get them to turn on:

  1. Make sure the key is in the ON position, and the engine is running.
  2. Switch headlights from ON to AUTO.
  3. Turn all power to the ignition switch OFF, back ON, and repeat step 2.
  4. If after step 3, the headlights still don’t come on automatically, then troubleshoot power going to the switch and wiring.
  5. If all power checks out, test the headlight switch for proper operation.
  6. Please contact a dealership for further assistance if your bike’s lights are not coming on automatically; this is a safety issue, and unsafe to ride without lights.

Remember that running lights turn off when the key is off when you manually turn them off.

What Is the Difference Between Motorcycle Flashing And Blinking Lights?

The main difference between motorcycle flashing and blinking lights is that flashing lights are only ON when the motorcycle is in motion. Blinkers, on the other hand, are always ON whether or not the motorcycle is in motion.

Another difference between motorcycle flashing and blinking lights can be attributed to their visibility from a distance away.

Blinking lights might be more noticeable than flashing lights depending on their color and how often they are blinking.

Why Do Motorcycle Headlights Blink?

Both can provide the most critical visual signals, like an on-coming vehicle and a hazard, but blinking lights provide a bigger indicator than flashing lights.

Here is a table of a few more differences:

FactorFlashing lightsBlinking lights
UseTo help them become more noticeable to other drivers around them.Let other road users know the driver intends to turn right or left.
LocationLocated at the rear tail section of the bikeThey are usually on either side of the motorcycle tail light cover.

How Much Does It Cost To Flash An ECU?

Electronic/Engine Control Module (ECM)$650
Powertrain Control Module (PCM)$80 – $150
Transmission Control Module (TCM) $75 and $250.
Brake Control Module (BCM or EBCM)$80-$120
Central Control Module (CCM)$900
Central Timing Module (CTM)$500
General Electronic Module (GEM)$300
Body Control Module (BCM)$572 and $601

How Do You Tell If Your Motorcycle ECU Has Been Flashed?

Exhaust Will PopLooking at the exhaust, a popping sound should be 30-60 seconds after starting the bike.

This is due to an air pocket created in the charcoal canister, pushing through the system and popping when it reaches atmospheric pressure.
Gas Efficiency Will IncreaseYou’ll get more miles per gallon of gas as ECU timing is set correctly for your gears.
Throttle Response Will Be FasterWhen the bike runs rich, there is more air resistance and a slower response.
Speed Will Not ChangeIt is possible to have a higher RPM where the ECU “thinks” it’s under load, and it holds the throttle at idle until a full load is reached or you let off the throttle (called over-revving).

This causes a loss of top speed. You have to re-programme the ECU before you can re-enable this advantage.
Rattle Will StopDue to the air push from the canister, the rattle in the dash area will disappear as you purge the canister out. If it does not, check for loose wire clamps and a loose canister connection.

What Lights to Use At Night On A Motorcycle?

HeadlightsHighlights your road visibility to other drivers, Must be used at night.
You can set it to high beams, low beams, or dipped beams.

Dipped headlights are required in some countries and may not be allowed in other states/provinces for safety reasons.
TaillightsServes as a warning light and lets other drivers know you’re behind them. 
Dashboard LightsWorn by law enforcement,bright and readable to other drivers.

May be used to let other drivers know you’re using your turn signal or moving in case your taillights aren’t working properly.
Dimmer Switches on Your BikeOverride the main headlight for additional illumination when needed.
Hazard LightsNeeded to warn other drivers that your motorcycle is disabled or stalled on the side of the road and could be a threat to other drivers.
ReflectorsReflect light from your bike to ensure your safety, as well as those of others in your area.

Keep in mind that some states may not require the use of reflectors. Check your local laws before attaching reflective strips to your bike.
MirrorsDistant, long-distance visibility and You can use it on your bike and by other riders to give them a better view of the road ahead.

Flickering Headlights, tail lights and gauge lights- The Difference

FactorFlickering HeadlightsTail lightsGauge lights
BatteryThe battery is charged, but you did not turn it onThe battery is charged and turned on, but you need to start the bike.The battery is low, and you need to charge it.
Fuel PumpThe pump is not turned on but is chargedThe pump is turned on and working, but the bike doesn’t have fuelThe fuel pump has run out of fuel, and you need to replace it.
IgnitionThe ignitions run when you turn the key On, but not all of the 3 ignitions are turned On.A couple of points light up in the lights at startup.

But for whatever reason, no more than two, then all three, then a few seconds later, none again.
The gauge lights are solid and usually work.
Air Ride SystemNot working properly and needs a replacementThe airbag is working properly, and you have an airbag light on.Gauge lights usually work and don’t need replacement.
Brake Lights (pedal feeler)The pedal feeler does not work normally and needs replacementThe pedal feeler is working but means nothing and doesn’t help you stop successfully.The gauge lights (if they’re still working) often don’t light up all the time;

Sometimes, they go out completely when you turn on the bike.
Brake LightsThe brake lights do not flash normally while braking and need replacement.The tail lights do not flash, but the stop lamps don’t either.

The indicator light doesn’t work, but if you turn left, it goes out as though it’s on.
The gauge lights do not work and often go out when you turn on the bike.
Why Do Motorcycle Headlights Blink?

Daylight MOT Vs.Fog Lights- Differences

FactorDaylight MOTFog Lights
Cost£29.65$62 and $73
UseServes to make your bike more visible during the dayUsed in the fog when visibility drops below 100 meters
BulbLight-emitting diodes (LEDs).Halogen bulbs
VisibilityThey are always just bright enough to illuminate the contours of your vehicle.Visibility is less than 50 meters
ColorThey should be whiteThey should be white or yellow
NeedThey are not compulsoryCompulsory


Motorcycle headlights and taillights are essential, and you must use them during the night. Ensure you use your motorcycle’s correct headlight, taillights, and other lights.

If you have lights that do not work, check for a burnt-out bulb or broken and loose connections.


Hi! I' am Tom. I faced many questions from customers about different products, and there was hardly any help on the internet. After learning all the things about these products as a manager the hard way, I decided to start a blog and help other people.

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