How to Change Rear Turn Signal Bulbs: Steps and FAQs

The rear turn signal alerts the driver behind when you’re turning, so if its bulb starts to malfunction or dim, don’t think twice about changing it. Otherwise, you’ll have a hard time communicating with other drivers, increasing the risk of mishaps on the road.

How to Change a Rear Turn Signal Bulb

Changing the rear turn signal bulb is a relatively simple task, so if you’re confident with your auto repair know-how, you can do it yourself.

Before starting, it’s crucial to know the two main types: wedge-base bulbs and bayonet-base bulbs.

Wedge-base bulbs are named as such because the bulb inserts into the socket like a wedge. On the other hand, bayonet bulbs are made of metal, and their tip inserts into the electric connector and is shaped like a cylinder.

Make sure you get the right bulb type for your ride. Once you have one on hand, you can follow the steps below to get started. Note that the process could vary depending on the vehicle.

• Step 1: Put on gloves for protection while you work.
• Step 2: Park your vehicle on a flat surface and turn off the engine.
• Step 3: Open the trunk or rear hatch to access the tail light assembly.
• Step 4: Locate the tail light assembly and identify the bulb that needs replacement.
• Step 5: If your vehicle requires you to remove the tail light assembly to access the bulb, do it carefully by removing any screws or clips holding the assembly in place.
• Step 6: Remove the assembly to access the bulb sockets.
• Step 7: Twist the bulb socket counterclockwise to remove it from the tail light assembly.
• Step 8: Remove the old bulb from the socket before inserting the new one into the same socket.
• Step 9: Place the bulb socket back into the tail light assembly and twist it clockwise.
• Step 10: Turn your vehicle’s headlights and turn signals on to test the new bulb.
• Step 11: Once you confirm the bulbs are working, reattach the tail light assembly (if you removed it) to the vehicle using the screws or clips you removed earlier.
• Step 12: Close the trunk or rear hatch of the car and dispose of the old bulb.

The way to insert the new bulb into the socket depends on the type of bulb you’re using. For wedge-base bulbs, you’ll have to push down until you hear a click. On the other hand, you’ll need to push and twist bayonet bulbs.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: Some vehicles have dedicated bulbs for the turn signals and others use the same bulb for both tail lights, stop lights, and turn signals.

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Why Change a Busted Rear Turn Signal Bulb Immediately?

Once the bulb malfunctions or burns out, you and others can be at risk of an accident. Additionally, a broken tail light is considered a non-moving violation and a ticketable offense.

What Are the Signs of a Bad Rear Turn Signal Bulb?

Some symptoms of a bad turn signal include malfunctioning hazard lights, dim turn signal lights, and turn signal lights that work erratically. These issues indicate that it might be time to replace the turn signal bulb. Most modern vehicles will blink the turn signal very rapidly if a bulb is blown, either on the front or the rear.

Common Reasons Why Your Turn Signal Is Malfunctioning

Turn signals typically malfunction due to dead light bulbs, a disrupted bulb socket, a broken blink switch, or a blown-out fuse.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: Wedge type bulbs can look just fine (no broken filament) and still fail to function due to connection failure on the wedge where it connects to the socket. When in doubt, change the bulb.

Dead Light Bulbs

A burnt light bulb is arguably the biggest reason your turn signal won’t turn on. Luckily, it’s also the easiest to fix because you only need to replace the bulb(s) for your turn signal to function again.

While the lifespan of turn signal bulbs typically depends on how often you use them and how you drive, they can last up to 4,000 hours.

Disrupted Bulb Sockets

Corrosion is normal in any metal component, mostly due to moisture or age. Once the bulb sockets start oxidizing, the rust could negatively affect the turn signal.

The rust disrupts the contact between the socket and the bulb, as well as the circuit, causing the blinkers to malfunction. Similarly, debris could also block the connection.

Broken Blink Switch

To turn on your blinkers, you’ll need to use the signal switch, which is usually located to the left of the steering wheel. A broken switch won’t send signals to the blinkers, even if the bulb is new and the socket is functioning.

The usual causes of such problems include wiring or controller issues, but a switch stuck in position will also prevent you from using it. It’s usually best to leave this type of issue to a mechanic.

Blown Fuse

Blown fuses could indicate different problems, though they could happen due to age and usage. Once your turn signal blows a fuse, expect the turn signal to stop functioning until you replace the fuse, and then you have to find out what caused the fuse to blow.

How Long Do Car Turn Signal Lights Last?

Typically, the turn signal bulb lasts up to 4,000 hours, but some will quite literally last the life of the vehicle. Some manufacturers also include the MTBF (mean time before failure) on the packaging or their website. It calculates the time before a piece of machinery/equipment fails.

How Often Should You Replace Turn Signal Bulbs?

There isn’t a set interval before replacing the turn signal bulbs. The best time to do it is when you notice the symptoms listed above or the MTBF is nearing.

Should You Change Both Blinkers at the Same Time?

It’s best to replace car bulbs in pairs to maximize efficiency and ensure consistent performance.

Not to mention, there’s a good chance they’ll dim simultaneously in the future. This is the perfect chance to have them both replaced instead of changing one bulb at a time.

In short, replacing bulbs in pairs means you don’t have to repeat the process as often.