How to Replace Wiper Blades and Headlight Bulbs Yourself

Observe the worn wiper blade in its natural habitat, smearing a gray stripe at eye level. Nearby, a tail light has gone dark, and its driver has no idea.

The challenge: three swaps, in order, until you can change wipers and bulbs without a shop. You need the owner's manual, an old towel and clean gloves.

Ground rules

• Find the size first. The manual lists blade lengths and bulb numbers. Some bulbs have the number printed on them too.
• Measure both wipers. The two blades on one windshield are often different lengths.
• Engine off, lights off.
• A swap counts when it passes its test. Fail one? Redo that step only.

Swap 1: wiper blades

Towel on the glass. Lift the arm. Press the release tab, slide the old blade off, slide the new one on until it clicks.

Hidden tip: keep one hand on the bare arm. It's spring-loaded, and with no blade on it the metal can snap back onto the glass hard enough to crack it, which is why Tesla's own service steps put a towel between arm and glass.

Check-in: run the washers. Chatter or a missed strip means the blade isn't seated. Click it on again.

Swap 2: a tail or brake light bulb

The manual shows how to reach the socket. Twist it out, swap the bulb, twist it back.

Check-in: have someone press the brake pedal. Alone? Back up close to a garage door and look for the red glow in the mirror.

Hidden tip: a turn signal that suddenly blinks fast? NAPA says a bad bulb is by far the most common cause. Hazards on, walk around, find it.

Swap 3: a headlight bulb

Pop the hood and find the back of the headlight housing. Unplug the connector, pull off the dust cover if there is one, and twist the old bulb out.

Gloves on before you touch the new one. Sylvania says never touch the glass, because skin leaves oil on it.

Do both sides. Sylvania recommends pairs because headlights dim over time, so one new bulb won't match the old one.

Check-in: try low beams, then high. One dark? Push the connector until it clicks.

The wobble

Swap three is where people want to quit. Some cars pack the headlight in so tight your hand barely fits.

That's the design, not you.

Read your model's steps first. Bumper has to come off? Stop. Xenon HID headlights too, since Saab's service manual warns their igniters put out over 23,000 volts.

Finish line

Swap three should feel like swap one with more parts in the way: find the size, protect, swap, test.

Paying shop labor for these is a waste of money.

Report back

Post your count and which swap fought you. Level two: check the wiper rubber every few months, since Consumer Reports found most blades fade after six to nine months. My younger son needed three tries to seat his first headlight connector.

Cheat sheet: wipers and bulbs

Start with swap one before you talk yourself out of it. Then report back with your count.