2002 LX470 Roof Leaking (1 Viewer)

Joined
Mar 23, 2014
Messages
93
Location
Bastrop, TX
I've just discovered that I have a roof leak! The water is collecting in the area where the rear AC control unit is and dripping into the cargo area. The area around the sunroof is bone dry.

Any idea where the water might be entering?

I've also noticed that there's a plastic trim piece flat on the roof very near where the water is collecting. Seems like that would be the logical entry point. What is that piece and how do I remove it without breaking it to see what's under it?

Any ideas?
 
Joined
Feb 18, 2020
Messages
68
Location
Tacoma
I'm surprised nobody has replied yet. I had a leak last year that I was convinced was windshield or door seal related that turned out to be blocked sunroof drains. I'd check all 4 drains to be sure water poured in the sunroof tray drains out all the way to the ground. You can snake them with weed whacker line or similar.

I've also heard of some folks having water intrusion through the roof rack mounts if bolts are loose, or need sealant. I believe the other common one is the upper brake light on top of the hatch, but I doubt that would wick all the way to your rear HVAC control area.
 
Joined
Mar 23, 2014
Messages
93
Location
Bastrop, TX
I'm surprised nobody has replied yet. I had a leak last year that I was convinced was windshield or door seal related that turned out to be blocked sunroof drains. I'd check all 4 drains to be sure water poured in the sunroof tray drains out all the way to the ground. You can snake them with weed whacker line or similar.

I've also heard of some folks having water intrusion through the roof rack mounts if bolts are loose, or need sealant. I believe the other common one is the upper brake light on top of the hatch, but I doubt that would wick all the way to your rear HVAC control area.
I'm hoping it's the sunroof drains. But I'm not optimistic because the entire area around the sunroof was bone dry. I quickly ran some weed wacker line down both the front drains. But I'm not sure I got all the way through them. And like I said, there was no sign of water near the front drains.

It was parked on a slight upward incline and I couldn't see the back drains. It's been raining today, so, I couldn't really inspect it too much. I'll dig into it more tomorrow, if it's not raining.

In the meantime, I'm hoping someone knows what's under those flat plastic trim pieces in the roof and whether the water may be entering there.
 

nakman

addict.
Supporting Vendor
Joined
Jul 30, 2003
Messages
2,512
Location
Broomfield, Colorado
That flat plastic trim piece, or drip edge cover, is not exactly water tight. So any water that is getting under in back there should be running down the outside of your hatch and tailgate, which are sealed by a single rubber gasket that surrounds the entire opening. Might inspect that gasket for any rips and tears? If you have one, it's possible to pull it off and just reorient it so the rip is in a different spot.

But my guess is the rear tailight- have you had that off recently?
 
Joined
Mar 23, 2014
Messages
93
Location
Bastrop, TX
That flat plastic trim piece, or drip edge cover, is not exactly water tight. So any water that is getting under in back there should be running down the outside of your hatch and tailgate, which are sealed by a single rubber gasket that surrounds the entire opening. Might inspect that gasket for any rips and tears? If you have one, it's possible to pull it off and just reorient it so the rip is in a different spot.

But my guess is the rear tailight- have you had that off recently?
Thanks.

I've had the truck for nearly 4 years and I haven't had the rear lights out since I've owned it. But, I don't think the leak is coming from the rear of the vehicle, since I park with the front up a slight incline. So, the water would have to run uphill to get to the rear AC control panel in the headliner over the driver side 2nd row seat.
 

nakman

addict.
Supporting Vendor
Joined
Jul 30, 2003
Messages
2,512
Location
Broomfield, Colorado
Ah ok when I saw rear AC I thought it was the stuff in the rear cargo panel... nevermind. So if you haven't messed with the roof rack either then I think you're back to chasing the sunroof drains.
 
Joined
Mar 23, 2014
Messages
93
Location
Bastrop, TX
Ah ok when I saw rear AC I thought it was the stuff in the rear cargo panel... nevermind. So if you haven't messed with the roof rack either then I think you're back to chasing the sunroof drains.
Speaking of roof racks, you probably know a little about those, huh? 😉

I'll probably be adding one of those in the near future. But, I gotta get this leak thing solved before I mess around with anything else on the roof.
 
Joined
Nov 4, 2007
Messages
10,656
Location
Colorado
If you look in my "Master link" under "Working on some others' 100 & 200 series:" "Inspecting a 100 series for "LEAKS" "Yeak" You'll find many leaks and what we did to stop them.

I've just discovered that I have a roof leak! The water is collecting in the area where the rear AC control unit is and dripping into the cargo area. The area around the sunroof is bone dry.

Any idea where the water might be entering?

I've also noticed that there's a plastic trim piece flat on the roof very near where the water is collecting. Seems like that would be the logical entry point. What is that piece and how do I remove it without breaking it to see what's under it?

Any ideas?

Most of the plastic molding in rain gutter (drip rial) are snapped in parts, removing some or all may help trace leak. The plastic gets old and brittle, so don't force. Best removed under a hot sun to soften.

The windshield side moldings are double sided tape, holding down in drip rail (or should be). Riveted onto "A" pillars. Which leaks here are confined travel down "A" pillar. Unless rust holes along top seal or open hole remaining after a poor windshield install.

Some methods to find a leak:

After a few dry hot sunny days, when moisture has dried up. Run a garden hose on the roof, while parked with front high. Controlling what ares get wet in stages, starting at rear. First on left side in rain gutter. Checking each point roof rack is secured. Also where can be secured, for the various (2 and 3 securing points) roof rack Toyota/Lexus has.

Moving forward with water, checking sun roof glass seal and rubber seal.

Keep water in each area long enough for leak to show-up inside. Don't stop at first found leak.

Soap bubbles method:

Create high pressure inside cabin, then watch outside for bubbles.

Few methods to accomplish this high pressure. Leaf blower taped/sealed into a window. Cabin fan to high with air circulating (fresh outside air).

Spray soapy solution on areas of possible leak, starting at rear working forwards. Watch for bubbles indicating a leak. A spray can of glass cleaner, can be used in place of soap water..

Watch for bubbles indicating leak point(s).
 
Joined
Mar 23, 2014
Messages
93
Location
Bastrop, TX
Where are the rear sunroof drain holes in the roof. I know where they come out under the truck. But I can't for the life of me find them in the roof.

Do I have to remove the headliner, or sunroof in order to be able to see the rear drain holes in the sunroof gutter?
 

awesomeissquid

SILVER Star
Joined
Jul 1, 2020
Messages
330
Location
Bay Area, CA
The rear drains are really hard to see. They are straight back on each side of the sunroof track. If you push some cord or something to try and clean the line you might have to try a few times to get it into the hole but it will get there eventually. I think I have a video I took when I was testing out a borescope. I’ll see if I can find it for you.
 

rfj62

SILVER Star
Joined
Jul 7, 2007
Messages
589
Location
West Chester, Pa
Where are the rear sunroof drain holes in the roof. I know where they come out under the truck. But I can't for the life of me find them in the roof.

Do I have to remove the headliner, or sunroof in order to be able to see the rear drain holes in the sunroof gutter?
I'm in the same boat. I replaced the sunroof gasket and want to blow out the drains before I reinstall.

Where do they come out under the truck?
 
Joined
Jul 21, 2010
Messages
1,020
Location
Northern VA
The rear drain comes out down the DS C-pillar, behind the sub-woofer and goes out bellow the jack.

You should see it when you are looking under the truck.

20210224_141355.jpg


20210224_143053.jpg


20210224_143616.jpg


20210224_143436.jpg


20210224_144517.jpg
 
Joined
Mar 23, 2014
Messages
93
Location
Bastrop, TX
I'm in the same boat. I replaced the sunroof gasket and want to blow out the drains before I reinstall.

Where do they come out under the truck?
The rear drains come out behind the rear tires. If you look under there, you'll see a rubber drain outlet.

Mine weren't fully clogged, so enough water got through them to help me find the outlet.

I couldn't find the drains in the sunroof gutter, so I just used a compressor to blow some low pressure air up through the one outlet that seemed restricted. Then poured more water in the sunroof gutter to test.

I didn't have much time to mess with it, but it seems to have improved.

Before I did anything, I poured water in the sunroof gutter and was able to see the water leaking around the rear AC unit. After I did what I described above, there wasn't water there when I retested. So, hopefully it's fixed for now.

I work out of town, so I'm not with the truck or I would go take some photos for you.
 

rfj62

SILVER Star
Joined
Jul 7, 2007
Messages
589
Location
West Chester, Pa
The rear drains come out behind the rear tires. If you look under there, you'll see a rubber drain outlet.

Mine weren't fully clogged, so enough water got through them to help me find the outlet.

I couldn't find the drains in the sunroof gutter, so I just used a compressor to blow some low pressure air up through the one outlet that seemed restricted. Then poured more water in the sunroof gutter to test.

I didn't have much time to mess with it, but it seems to have improved.

Before I did anything, I poured water in the sunroof gutter and was able to see the water leaking around the rear AC unit. After I did what I described above, there wasn't water there when I retested. So, hopefully it's fixed for now.

I work out of town, so I'm not with the truck or I would go take some photos for you.


Thanks, I'll do the same. @rrc swb photos were really helpful!

I can see the front drains up in the roof, but where do the exit the truck?
 

awesomeissquid

SILVER Star
Joined
Jul 1, 2020
Messages
330
Location
Bay Area, CA

Here is the view of the rear drains. The video is upside down unfortunately. I don't recall exactly where the front drains, but it is somewhere near the front wheel (either before or after).
 
Joined
Jul 21, 2010
Messages
1,020
Location
Northern VA
Thanks, I'll do the same. @rrc swb photos were really helpful!

I can see the front drains up in the roof, but where do the exit the truck?
When you scoot under the truck you should see it on the vertical panel... You should see it right away. It's pointing inward.

If you remove the jack and mount you can see it.
 
Last edited:

Users who are viewing this thread

Top Bottom