How to Fix a Car Mirror: Popped Out, Loose, or Stuck

A car mirror that popped out is really two different repairs. A rearview mirror that fell off the windshield is re-bonded to its metal mounting button with a two-part adhesive, and Permatex lists 30 minutes to mirror mounting strength for its kit. A side mirror whose glass is loose, or that will not adjust, is traced through clips, fuses, switches and motors, according to Ford’s 2014 Mustang workshop manual. This guide covers rearview button re-bonding, loose side mirror glass, mirrors that will not adjust, and heated and auto-dimming mirror faults.

Why Did My Car Mirror Pop Out?

Ford’s workshop manual for the 2014 Mustang (section 501-09, Rear View Mirrors) has a symptom chart for a mirror that vibrates or feels loose. It is written for one model, but the causes it lists are a useful checklist for any car.

• Mounting nuts loose: Ford’s action is to tighten the exterior mirror mounting nuts to the specified value.
• Glass not seated: compare the left and right mirror glass, then press the center of the glass up, down, left and right to check it is seated. If it is still loose, remove the glass and inspect the backing plate; if the plate is damaged, Ford installs new mirror glass.
• Motor mounting screws loose: remove the glass, inspect the motor mounting screws, tighten them if needed and reinstall the glass.
• Aftermarket air deflector or stone shield: remove it if possible and road test the car; Ford notes that these parts can cause vibration.
• Impact damage to the pivot or housing: Ford installs a new exterior mirror.

For a loose interior mirror still on the windshield, Ford says not to remove it: first attempt to fully seat it. If it still vibrates, remove and reinstall it, and if that fails, install a new mirror.

What Kind of Car Mirror Are We Talking About?

The repair depends on which mirror came loose. Ford’s manual lists the parts of a power side mirror: the adjustable mirror glass, the glass adjustment motors, the mirror cover, the housing and the control switch. Ford’s 2014 Mustang also has optional heated mirror glass.

• Side mirror glass: on that Mustang the glass sits on the mirror motor and is held by retaining tabs, and the tabs snap onto the mirror motor.
• Whole side mirror: on the Mustang the mirror is held to the door by 3 nuts, tightened to 9 Nm (80 lb-in). That torque is for that car only; other models differ.
• Interior rearview mirror: Ford describes it as mounting to a bracket at the upper center of the windshield glass, with optional auto-dimming versions.

For a side mirror that is hanging off the door, see our dedicated guide, How to Fix a Car Side Mirror That Fell Off (Snap-Fit vs. Glue), and our step-by-step side mirror repair guide. If the whole mirror has to be replaced, this replacement side mirror comparison covers the options.

Tools and Materials You’ll Need

What you need depends on the scenario. For a rearview mirror button, the Permatex rearview mirror adhesive kit data sheet lists the following:

• Two-part adhesive (an adhesive tube or pencil and a cleaner/activator towelette)
• A safety razor to scrape old adhesive off the windshield and button
• Fine grit sandpaper to sand the button’s mounting surface
• An alcohol prep pad to clean the windshield and button
• A felt-tip marker or crayon to mark the button position on the outside of the windshield
• A cloth to wipe off uncured resin

For side mirror glass, Ford’s procedure calls for a thin flat-blade screwdriver and a shop towel to place between your hands and the glass.

If you want to compare adhesive kits first, see our car mirror adhesive roundup. Our mirror tape guide covers tape-based mounting, and how to remove adhesive from car glass helps with leftover residue.

How to Fix a Car Mirror That Popped Out: Step-by-Step

Pick the scenario that matches your mirror.

Scenario 1: Fixing a Popped-Out Side Mirror Glass

Safety flag: Ford’s manual warns to place a shop towel between your hands and the exterior mirror glass during mirror service, in case the glass breaks. Failure to do so may result in serious personal injury. The steps below follow Ford’s procedure for the 2014 Mustang; check how your own glass is retained before you start.

1. Inspect the glass and its backing plate. If the backing plate is damaged, Ford installs a new mirror glass.
2. If the glass is heated and has electrical connectors, connect them before seating the glass. Ford’s procedure says to connect the electrical connectors, if equipped.
3. Place a shop towel between your hands and the glass.
4. Press firmly in the center of the glass while manually rotating the glass in all directions until all of the retaining tabs are snapped onto the mirror motor. Ford notes you will hear an audible click.
5. Press the center of the glass up, down, left and right to confirm it is seated. If it is still loose, Ford removes the glass and inspects the backing plate.

To take a seated glass off, Ford positions it fully upward and inboard, inserts a thin flat-blade screwdriver at the lower outboard side, and releases the retaining tabs from the lower outboard side to the lower inboard side. Do not clean mirror glass with an ice scraper, razor blade, abrasive pad or harsh chemicals, which may damage the glass or housing.

Scenario 2: Reattaching an Interior Rearview Mirror to the Windshield

If the mirror head has simply slipped off a bracket that is still bonded to the windshield, Ford’s mounting procedure for one mirror type is to slide the mirror mount over the windshield bracket from the top; an audible click means it has fully seated. If the metal button itself has come off the glass, the Permatex rearview mirror adhesive data sheet gives this procedure for a two-part kit. It says the adhesive permanently bonds metal mirror buttons to windshields and is not intended for bonding plastic buttons.

Safety flag: this repair bonds to the windshield. Permatex warns not to try to remove an incorrectly mounted button because the windshield may break or cause personal injury. Ford also notes in its mirror removal procedure that the windshield must be at room temperature, otherwise damage to the windshield glass may occur.

1. Read all of the directions before you start. Permatex says repairs can ideally be made at 50 F to 75 F, and repairs at lower temperatures take longer to cure.
2. Remove the mounting button from the mirror bracket. On the outside of the windshield, mark the spot where the button was mounted with a felt-tip marker or crayon.
3. Scrape all old adhesive off the windshield and the button with a safety razor, taking care not to gouge the button.
4. Put the button on a flat, hard surface and gently sand its mounting surface with fine grit sandpaper in a circular motion. Clean both the windshield and the button with the alcohol prep pad.
5. Apply the activator to the inside of the windshield where you marked the spot, in a circular motion, overlapping the mark by at least 1/2 inch. Let it dry for at least 2 minutes and do not touch the glass after the activator has been applied.
6. Cut the cap off the adhesive tube and apply one drop to the center of the button. Permatex’s own reminder: more is not better.
7. Immediately apply the button to the windshield with the correct side up (usually the rounded side). Hold it firmly against the windshield for at least 1 minute without moving it, then allow it to set for at least 30 minutes.
8. Mount the mirror bracket onto the button, then clean the marking off the outside of the windshield with alcohol.
9. Wipe off any uncured resin with a cloth; any remaining uncured resin can be cleaned up with a cloth saturated with alcohol.

Cure time depends on the adhesive. The Permatex data sheet lists handling strength in seconds and mirror mounting strength in 30 minutes; the Loctite kit above has its own instructions.

Camera or sensor behind the mirror: in the Mustang manual, installing a new mirror on a car with lane departure is followed by camera alignment with a scan tool.

Side Mirror Stuck and Won’t Move? Here’s a Different Problem

A mirror that has not come loose but will not adjust is an electrical or motor problem, and adhesive will not fix it. Ford’s symptom chart for the 2014 Mustang splits the diagnosis like this:

• Both mirrors inoperative: fuse, wiring, terminals or connectors, and the exterior mirror control switch. The manual’s test for the control switch includes verifying that a 7.5 amp fuse is OK.
• One mirror inoperative: wiring, terminals or connectors, the control switch, the mirror motor and the mirror.
• One mirror does not operate correctly: the same list: wiring, switch, motor and mirror.

In Ford’s description, the position of the exterior mirror control switch (LH or RH) determines which mirror glass is controlled, and the switch supplies voltage and ground to the selected mirror motor when you move it up, down, left or right.

The mirrors use a jumper harness that is integral to the exterior mirror; if it has a concern and cannot be repaired, Ford installs a new exterior mirror.

If a fuse is the suspect, read why car fuses keep blowing first.

Mirror Glass Loose or Popping Up and Down

A mirror that vibrates or feels loose is the “Mirror vibrates/loose” row in Ford’s chart: check the mounting nuts, the seating of the glass and the motor mounting screws, which need the glass removed to inspect.

Heated and Auto-Dimming Mirror Problems

• Heated side mirrors: on the 2014 Mustang they only operate when the rear window defrost is on, and Ford’s test checks the mirror glass temperature, then the rear window defrost. Possible sources it lists are the fuse, wiring, glass, the mirror and the rear window defrost system.
• Auto-dimming interior mirror: it has two photoelectric sensors, and if they are blocked it may not work correctly. Ford lists stickers, window decals, tags, fold-down screens and non-OEM window tinting as blockage sources. Covering a sensor with a finger or hand is not adequate for testing, per Ford.

When to Call a Professional

Stop and get a shop or dealer involved when any of the following applies:

• A rearview mirror button was mounted incorrectly. Permatex says not to attempt removal because the windshield may break or cause personal injury.
• The glass is cracked, or the backing plate is damaged and you cannot get replacement glass.
• The mirror has a camera or sensor, or lane departure, since the Mustang manual calls for scan-tool camera alignment after a new mirror is installed.
• Fuse, switch and visual checks do not restore a power mirror. Ford’s remaining tests use a multimeter and vehicle-specific wiring diagrams.
• The mirror housing or pivot has impact damage; Ford installs a new exterior mirror in that case.

The federal standard for rear visibility, 49 CFR 571.111 (FMVSS 111), requires each passenger car to have an inside rearview mirror of unit magnification (S5.1) and a driver’s side outside mirror of unit magnification (S5.2.1). Check your state’s rules for driving with a damaged or missing mirror. Our FMVSS 111 mirror requirements guide goes through the standard in more detail.

Common Mirror Problems and Where to Look First

Symptom	First check	Source
Interior mirror loose on its mount	Fully seat the mirror; if still loose, remove and reinstall; then replace	Ford 2014 Mustang manual
Rearview mirror button off the windshield	Two-part adhesive and activator; hold 1 minute, set 30 minutes	Permatex data sheet
Side mirror glass loose	Press center up, down, left, right; inspect backing plate	Ford 2014 Mustang manual
Side mirror vibrates	Mounting nuts, glass seating, motor mounting screws	Ford 2014 Mustang manual
Both power mirrors dead	Fuse, wiring, control switch	Ford 2014 Mustang manual
One power mirror dead	Wiring, control switch, motor, mirror	Ford 2014 Mustang manual
Heated mirror not heating	Fuse, wiring, glass, mirror, rear defrost system	Ford 2014 Mustang manual
Auto-dimming mirror stays clear	Blocked sensors; fuse; circuit	Ford 2014 Mustang manual

Related repair guides: fixing a broken car door handle, DIY car interior upgrades and removing a car door panel.

What This Guide Does Not Cover

• Repair prices; ask a shop or dealer for an estimate.
• Voltage and resistance testing of mirror circuits, which belongs to the maker’s service diagnostics.
• Vehicle-specific steps for makes and models other than the sources named here.

This guide is general information, not professional repair advice. Mirror glass, windshield bonding and vehicle wiring can injure you or damage the car if done wrong.

Keep reading

• How To Fix A Car Window That Won’T Go Up (Quick Solutions)
• Car Glass Repair and Replacement: Windshield, Mirror and Touchscreen Options
• Car Door Stuck Closed? How to Open It Fast (DIY Fixes)

Frequently Asked Questions (FAQ)

How long does mirror adhesive take to dry?

It depends on the product. The Permatex rearview mirror adhesive data sheet lists handling strength in seconds and mirror mounting strength in 30 minutes, with the button held firmly for at least 1 minute and then left to set for at least 30 minutes, ideally at 50 F to 75 F. Lower temperatures take longer to cure. For any other adhesive, use the times printed on its own packaging.

Can I mount a rearview mirror button again if I put it on crooked?

Do not pull it off. The Permatex data sheet says to buy a new button and mount it directly over the top of the incorrectly mounted one with the same procedure, and warns that trying to remove the incorrectly mounted button may cause the windshield to break or personal injury.

Why will my side mirror not adjust?

Ford’s 2014 Mustang workshop manual splits the problem by symptom. If both mirrors are inoperative, the listed sources are the fuse, the wiring, terminals or connectors, and the exterior mirror control switch. If a single mirror is inoperative, the sources are the wiring, the switch, the mirror motor and the mirror itself.

Why does my auto-dimming mirror stay clear?

Ford’s manual says the two photoelectric sensors in an auto-dimming interior mirror can stop it working correctly when blocked, and lists stickers, window decals, tags, fold-down screens and non-OEM window tinting as sources of blockage. It also says the mirror returns to its high reflectance mode whenever the vehicle is in reverse, so a mirror that clears in reverse is working as designed.