2017-2022 Genesis G90 Rear Door Glass: Acoustic Properties and Replacement Guide

Symptoms of Failure

Failures of the rear door glass can be separated into two categories: problems with the glass itself, and problems with the components that move it. It is important to know the difference before buying parts.

Glass-Specific Failures

• Cracks or Shattering: Unlike typical tempered glass that shatters into thousands of small pieces, the laminated acoustic glass in the G90 is designed to crack but hold together, much like a windshield. This is usually caused by a significant impact from an accident or foreign object.
• Scratches: Deep scratches can be caused by debris getting trapped in the window seals or by improper cleaning. Scratches can be visually distracting and cannot be easily repaired.
• Delamination: In rare cases, the layers of the laminated glass can begin to separate. This often appears as a milky, bubbly, or hazy area, usually starting at the edges of the window. This compromises both the appearance and the acoustic-dampening properties of the glass.

Symptoms of a Bad Window Regulator or Motor (Not the Glass)

If your glass is physically intact but will not operate correctly, the problem is likely the window regulator or motor. 🎬 See how to replace a faulty window regulator in this video. Symptoms include:

• The window moves very slowly or struggles to go up or down.
• Grinding, clicking, or popping noises come from inside the door when you press the window switch.
• The window falls down into the door and will not stay up.
• The window operates from the driver's master switch but not the rear door switch (or vice-versa), which usually points to a bad switch, not the motor or glass.
• The window does not move at all, and you hear no sound from the door. This could be a fuse, switch, or dead motor.

Known Issues, TSBs, and Recalls

For the 2017-2022 model years, there are no widespread known issues, technical service bulletins (TSBs), or recalls from the National Highway Traffic Safety Administration (NHTSA) that specifically concern the movable rear door glass. The part is generally considered reliable, with failures typically resulting from external damage.

Buying a Used Rear Window Glass: What to Check

A used OEM rear door glass is an excellent value, as it provides the exact same acoustic performance and tint as a new part for a fraction of the price. However, careful inspection is key.

1. Verify It's Acoustic Glass: This is the most important step. A non-acoustic, standard tempered glass from another vehicle will not fit properly and will dramatically increase cabin noise. Look for markings on the glass; acoustic glass is often labeled with an 'A', 'AC', or a symbol of an ear. Ask the seller to confirm the glass is from a G90 and is the original laminated acoustic type.
2. Inspect for Scratches: Hold the glass up to a light source and examine it from multiple angles. Run your fingernail over any suspect areas. A deep scratch that you can feel with your nail will be very visible once installed. Minor scuffs may be acceptable, but deep scratches are permanent.
3. Check for Delamination: Carefully inspect the edges of the glass. Look for any signs of a milky or bubbly appearance, which indicates the layers are separating. Do not purchase glass that shows any sign of delamination.
4. Confirm the Tint: The G90's rear windows have a factory privacy tint. A used OEM part will be a perfect match. Be wary of glass that has had aftermarket film applied, as it may be hiding scratches or be a non-OEM part. The film can also bubble and peel over time.
5. Check Mounting Points: Ensure the plastic clips or mounting points where the glass bolts to the window regulator are intact and not cracked or broken.

Cost Comparison

The cost to replace a rear door window on the Genesis G90 can vary based on the source of the part and labor rates.

Replacement Overview

Replacing the rear door glass is a moderately difficult job. While it doesn't require highly specialized tools, it demands patience and care to avoid damaging the interior door panel. A general repair guide for a related Hyundai Genesis shows the basic steps.

• Difficulty Rating: 3 out of 5
• Estimated Time: 1.0 - 1.5 hours
• DIY Feasible: Yes, for experienced individuals.

Basic Steps:

1. Remove the interior door trim panel. 🎬 Watch: Step-by-step guide to removing the G90 rear door panel. This involves finding and removing screws inside the door handle and armrest areas, then using plastic trim tools to carefully pry the panel off its clips.
2. Disconnect any electrical connectors for the window switch, speaker, and side sunshade (if equipped).
3. Carefully peel back the plastic or foam weather barrier to gain access to the inside of the door.
4. Temporarily reconnect the window switch and lower the window until you can see the mounting bolts through the access holes in the door's metal frame.
5. Loosen the bolts that clamp the glass to the window regulator.
6. Carefully tilt and lift the glass out 🎬 Watch this demonstration of a Genesis rear window glass replacement. of the top of the door frame.
7. Installation is the reverse of removal. Be sure to tighten the glass to the regulator securely and test the window's operation before reinstalling the door panel.

Frequently Asked Questions (FAQ)

Technical Specifications & Part Numbers

The part number depends on which side of the vehicle you need.

Key Specifications:

• Type: Laminated Acoustic Glass
• Features: Factory Privacy Tint