How to Identify and Fix a Leaky Sunroof

A sunroof is a wonderful feature to have in a vehicle. You get the open air feeling of a convertible with the weather protection of a hard top. But what happens when that sunroof begins to let the weather inside? Wet seats and soaked carpet are the results. Unfortunately a leaky sunroof is an all too common problem, but the solution is sometimes quite simple. Here’s how to identify and fix a leaky sunroof.

Identifying a Sunroof Leak

Obviously if you are sitting in your car when it rains and water starts pouring from the area around the sunroof, you have a leak. But sometimes the leaks aren’t so obvious. You may notice water on the floorboard or wet carpet. A sunroof leak can let water flow through interior panels like the headliner and pillar panels where it is unseen. If you’ve ruled out a clogged AC drain or leaky door seals, you may have a sunroof leak on your hands.

Sunroof Leak Causes

You can track down most sunroof leaks to these common issues:

Clogged Sunroof Drain

One of the most common causes of a car sunroof leaking is simply a clogged drain. For many vehicles the area around the sunroof opening has a raised edge to catch any water that may get past the main sunroof seal. It is basically a drain pan with a sunroof sized hole in the middle. Water is supposed to flow from the catch pan into drain hoses (usually in the corners of the sunroof opening), which are routed through the body of the car and to the ground. As time passes, debris like leaves and dirt can find their way into the drain openings and clog the drain tubes. Once the drain tubes are clogged, the area around the sunroof will fill with water and spill over into the interior.

Damaged Sunroof Seal

The first line of defense against water is the seal around the sunroof panel itself. While most seals are not designed to completely stop water from getting into the area around the sunroof opening, the seal does hold back a fair amount of water from entering. Sun and heat can eventually damage the seal causing it to dry out, crack, deform or wear down at any areas that contact the body. When this seal is seriously compromised, too much water can get in and overwhelm the sunroof drains.

Damaged Mechanism

Your sunroof mechanism is a complex component that must both slide and lift/lower your sunroof panel in and out of position. It relies on motors and relays working in perfect harmony. The sunroof track itself is also precisely designed for smooth movement and solid placement of the sunroof panel. If any of these parts are damaged, worn or misaligned, the sunroof panel will not move to the desired position. Often a sunroof motor will break and leave the sunroof open, making for a frantic manual override to keep out the weather. But the sunroof may also appear to function properly while not moving to the correct closed position. If this happens, there is possibly a gap between the sunroof seal. The sunroof panel may also not close flush with the roof causing a channel for water to travel.

How to Fix a Leaking Sunroof

Once you have investigated your sunroof leak and found the culprit, it is time to learn how to fix a leaky sunroof.

Cleaning the sunroof drains is the simplest car sunroof leak repair. Locate the sunroof drains. There is a potential of up to four drains depending on the vehicle with some not easily visible. Referencing a vehicle repair manual can help you find all the drain locations. It is tempting to grab a compressed air hose and blow out the drain tubes, but that is a mistake. Blowing compressed air into a clogged tube can cause the tube to pop off an internal connection leading to a time-consuming interior panel disassembly. The simplest method for clearing a sunroof drain is with a piece of string trimmer line. String trimmer line is stiff enough to push through a blockage while also following the drain tube twists and turns. Now you can move onto your leaking sunroof repair:

1. Dip the tip of the trimmer line in dish soap to help it slide along the drain tube.
2. Feed the trimmer line into the drain tube opening feeling for any resistance. When resistance is felt, push gently on the trimmer line, then pull back gently.
3. Move the trimmer line in and out of the tube until the clog is no longer felt.
4. Remove the trimmer line and pour a small amount of water down the drain tube. The water should exit underneath the vehicle. If the water does not flow out, repeat the trimmer line technique until all clogs are removed.

If the drain tubes are clear, turn your attention to the sunroof itself and the mechanism. Clean the sunroof seal with a soft cloth and apply silicone lubricant spray to help it stay flexible. Observe how the sunroof moves while it opens and closes, noting any places where it stutters or does not move smoothly. If the movement is not smooth give the sunroof panel tracks a spray with the same silicone lubricant spray. If the sunroof does not close flush with the roof panel, it may need an adjustment.

If there is no time for proper repairs, a temporary fix for leaking sunroof problems is to simply seal it shut. Good quality 2” wide paint masking tape works just fine. Masking tape will hold through a rainstorm while you make plans for an adequate car sunroof leak repair. Masking tape also releases easily and reduces the chance of harming your vehicle’s finish. Once the sunroof is taped shut, you can place a piece of masking tape over the sunroof button to remind yourself not to use it.

Sunroof Leak Repair Costs

So how much does it cost to fix a leaking sunroof? If you are a DIYer with a stocked garage, the cost of repair is possibly only your time for something simple like a clogged drain. But if the issue is more serious, the sunroof leak repair cost could reach into the hundreds or even thousands. Modern vehicles with panoramic sunroof panels are wonderful for feeling the sun on the road, but these are very complex mechanisms. A leak in one of these mammoth panels could take hours for a technician to repair.

You may wonder if car insurance covers leaking sunroof issues, and the answer is “maybe” depending on your insurance coverage. Read your insurance policy carefully, consult with your insurance agent and weigh the cost of your deductible. In some cases, damage caused by a sunroof leak is covered by insurance, but the likelihood is small.

Check out all the sunroof products available on NAPAonline, or trust one of our 17,000 NAPA Auto Care locations for routine maintenance and repairs. For more information on how to fix a leaky sunroof or figuring out how much does it cost to fix a leaking sunroof, chat with a knowledgeable expert at your local NAPA Auto Parts store.

Photo courtesy of Pexels.