One of the many annoying realities of car ownership is the fact that a car’s rearview mirror is, by necessity, attached to the inner windshield with adhesive. The adhesive is typically a strong one — it’s usually easier to break the glass than to detach the mirror — but heat and humidity can work together to weaken its bond with the glass. And there are few places that concentrate heat and humidity more than an enclosed car. Even in mild weather, this can break loose the rearview mirror.
If it happens that you’re presented with a dangling mirror one day when you unlock your car, don’t despair. It’s just one of many small automotive irritations, but it can be dealt with — and you don’t have to pay a mechanic to fix it.
Tools and Materials Required
- Rubbing alcohol
- Paper towels or a soft cloth
- A wax crayon or marking pencil
- A flat-bladed scraper
- A flat-head screwdriver
- A small pair of pliers
- A mirror reattachment kit (NAPA and 3-M make good ones)
NOTE: Humidity can sabotage your efforts to replace your rearview mirror. If possible, wait for a particularly dry day before attempting this procedure.
- Use the scraper to scrape clean the area where the mirror was formerly attached. If the scraper blade is sharp enough, even the toughest adhesive will yield to it.
- Pour some alcohol onto a paper towel or cloth and use it to wipe down the area you’ve just scraped clean in order to remove any grease, oils, or remaining adhesive. Allow the windshield to dry for at least five minutes.
- Examine the attachment point of the mirror. You’ll notice the presence of a small U-shaped button in the receptacle of the attachment point. It is imperative that you remove this button. In some cases, it is secured with a small screw, which it will be necessary for you to remove first. Usually, however, it’s simply snapped into place. In this instance, use the pliers to press down the metal flange holding it in, and use the screwdriver to pry out the button.
- Once you’ve removed the button (however you managed it), very carefully use the scraper to remove all traces of adhesive from its face. Then clean the button with alcohol. Allow it to dry for five minutes.
- When the button is dry, place it against the spot on the windshield where you’d like the mirror to be attached. Make sure that it’s in the appropriate spot, because once it’s on, it’s not something you can easily remove again.
- Make sure that the curved end of the U-shaped button is facing UPWARD. Then use the crayon or marker to trace around the button. When you remove the button, the area where you want to install it will be marked. Set the button aside for now.
- Open the repair kit and CAREFULLY read the instructions. The kit usually includes a small tube of adhesive, a vial of adhesive activator, and sometimes a spare button, in case you’ve lost yours. Fortunately, the whole set-up doesn’t cost more than a few dollars.
- Remove the activator container. The fluid inside is absolutely necessary to activate the adhesive; without it, the glue is just noxious-smelling goo. In most cases, the activator is packaged in a small plastic vial consisting of a reservoir of fluid separated from a swab by a thin piece of glass (sort of like old Mercurochrome swabs, if you can remember back that far). Squeeze the vial to break the glass, allowing the fluid to soak the swab.
- Liberally paint the marked area on the windshield with the activator. If you like, you can coat the inner face of the button as well. Allow both surfaces to dry for at least five minutes.
- Remove the adhesive tube from the kit and cut off the tip with the scissors. Squeeze one large drop of the adhesive onto the center of the inner face of the button. Don’t overdo it.
- Place the gluey side of the button onto the marked area of the windshield, curved end upward. (REMEMBER, if you get this wrong, it’s extremely hard to fix.) Press it against the windshield for at least sixty seconds; hold on a bit longer if you can.
- When you release the pressure, the button should be affixed to the glass. If it is not, repeat steps 1-11; you should have enough material left for one retry. Once the button is on the windshield, wait at least an hour before continuing with this procedure.
- After waiting an hour or more for the adhesive to set properly, you can try to reattach the mirror. Carefully slide the attachment receptacle onto the button and push down until you hear a click. In some instances, you may need to fasten the button to the mirror with a small screw (see Step 3).
- Clean the mirror with alcohol and adjust it to your liking. Then clean the area around the attachment point. Viola, you’re done!