Please do and let us know your results. I'm experiencing the same water infiltration on the passenger side albeit the drain is partially open/blocked. I haven't however removed the plastic panels that you evidently have. Have you any pics of the procedure?


Will

 

I will respond more thoroughly hopefully tonight when I have time to address the issue, upload pics (including borescope pics of the hole at the bottom of the 'reservoir' that is created when it -- the hole -- plugs up) and let it get rained on or soaked with a hose to verify that I have solved it. I accessed through the driver's side outer kick panel -- the one just to the outside of the parking brake. I personally didn't want to work in any area with an airbag so I did not explore and take off the pillar cover. The bubbling sound of air through water when blowing air into the driver's side sunroof drain was the key to finding this area (pulsed air in top drain using 1/4 inch tubing, which fits into the hole, but don't try to push it too far in, with compressed air at 30psi).

WARNING, the disassembly that I did involved disconnecting and shifting 9-10 connectors in that large group inside the kick panel so that the inset blue plastic box could be removed for access to the concealed area, so if you are not comfortable with this (DISCONNECT THE BATTERY NEGATIVE FIRST!), you may not want to take the risk of possibly breaking one of a multitude of wires. I am going to see if there is an easier way to do this that doesn't involve as much disassembly and I want to take a good look at the passenger side too since it may not be weeping through the seam as fast as the driver's side does now.

Be patient and put a tarp on your vehicle to keep the inside dry. I ended up taking out the second and third row seats in order to get the carpet thoroughly dry. Peeled back and propped up the front two sections to dry them and also temporarily popped out the rubber hole plugs in the bottom of the two front foot areas to allow any leakage to drain better. Hasn't been fun or easy or quick given all of the rain that we have been getting.

 

I will respond more thoroughly hopefully tonight when I have time to address the issue, upload pics (including borescope pics of the hole at the bottom of the 'reservoir'

Can't wait for the pics and lessons learned, yours will be the first!

 

Many thanks, FT. I'll await your findings. I, too, used compressed air through a quarter inch pvc tube. May have used too much pressure, however, with 90psi. And heard the burbling after which more water ( which I poured thru the drain) dispersed on the carpet. Seems the villain for me in this scene is the fine tree pollen that has gone into the drain tube and blocked it.



Will

 

IIRC this is a common issue on gen2 Highlanders. Comes down to missing body plugs at the chassis rails underneath the rear bumper cover.

I've fixed a couple for customers, replace the body plugs with new OEM and apply silicone to seal them and hold them there.

 

We are definitely having a different issue, but I may also explore this one on my wife's vehicle just for future prevention.

One youtube poster made a video of drilling underneath on the driver's side to open up the area where water was being trapped. May have resort to that approach finally.
Will

DON'T DRILL! I thought that I would have to do that also. He must have basically drilled another hole into this area and it didn't look easy or fun. You may want to try using a piece of coat hanger bent in just the right arc or shape and go through the ground screw hole. I assume that passenger and driver's side are similar. The drain tube only goes towards the bottom of this enclosed space, that's why the hole clog can't be blown clear with air.

Can't wait for the pics and lessons learned, yours will be the first!

Pics uploaded and it rained about an inch last night . . . with both front foot areas dry! Even had the nose facing downhill so the front sunroof drains got all the water. Will get to finally put the interior back together this weekend.

 

The pics tell the story

WARNING: Damage may easily occur if you do what I did. Disconnect the battery negative first, but still no guarantee of damage prevention. It worked for me, it may fail miserably for you.

This is the box inside the driver's side kickpanel that I wanted to explore behind:
https://www.toyotanation.com/forum/attachment.php?attachmentid=240124

This is with the box tilted out of the way and with a coat hanger probing the depths:
https://www.toyotanation.com/forum/attachment.php?attachmentid=240122

What I saw when I inserted the borescope into the space below where the box used to be:
https://www.toyotanation.com/forum/attachment.php?attachmentid=240126

A close up of the hole that plugs with dirt due to the double wall construction at the bottom of the hole:
https://www.toyotanation.com/forum/attachment.php?attachmentid=240118

After stirring inside the hole with the coat hanger, SUCCESS! Water once again weeps out the proper location.
https://www.toyotanation.com/forum/attachment.php?attachmentid=2401201

I'm thinking that if just the ground screw to the body is removed from the lowest point in the bottom group of cables that are not routed to the box, that there may be just enough room to use a properly shaped length of coat hanger to clear the plugged hole without having to disassemble and risk as much as I did. This would also apply to the passenger side. When initially probing with the coat hanger, I could definitely feel the hole as the end of the coat hanger traversed the bottom of the enclosed space. Explore at your own risk and definitely disconnect the negative at the battery first! Good luck!

I may also try to get some images of the rear drains and the tight spaces that need navigated to get to them. Borescope cost about $100 after a 25% off special on-line order. A Greenlee wireless one that could record video would have been nice.

 

I'm thinking that if just the ground screw to the body is removed from the lowest point in the bottom group of cables that are not routed to the box, that there may be just enough room to use a properly shaped length of coat hanger to clear the plugged hole without having to disassemble and risk as much as I did. This would also apply to the passenger side. When initially probing with the coat hanger, I could definitely feel the hole as the end of the coat hanger traversed the bottom of the enclosed space. Explore at your own risk and definitely disconnect the negative at the battery first! Good luck!

FT, Following your advice I relented on the drilling. I had removed, at great effort, both of the connector boxes on the psgr side. Finally, I dangled a small LED flashlight into the cavity and held a mechanics mirror above and was able to see the small hole where water drains out. I rigged, to a small vacuum, a plastic tube about 1/2 in. interior diameter and cleaned out the debris in the cavity. Strange thing, the hole has a metal bottom but water still drains out somehow. It's been raining here for several hours - just checked and no water on the floor.
Thanks again for your pictures and consultation.


Will

 

Further pics

Obvious labels in photos and file names. The end of the coat hanger was wet when I pulled it out after initial probing. The end of the borescope was also wet after going in for the close-up of the hole. Put water in with turkey baster after stirring the hole with the coat hanger and it came out the weep seam instead of filling the 'reservoir' until it cam out a hole near the bottom connectors. Good luck to everyone who gets this body hole plugged with junk -- the key is hearing the bubbling sound when blowing out the front sunroof drains. Water may slowly seep through the plug, but man, it flows so much faster when you clear that darn hole.

 

Obvious labels in photos and file names. The end of the coat hanger was wet when I pulled it out after initial probing. The end of the borescope was also wet after going in for the close-up of the hole. Put water in with turkey baster after stirring the hole with the coat hanger and it came out the weep seam instead of filling the 'reservoir' until it cam out a hole near the bottom connectors. Good luck to everyone who gets this body hole plugged with junk -- the key is hearing the bubbling sound when blowing out the front sunroof drains. Water may slowly seep through the plug, but man, it flows so much faster when you clear that darn hole.

Oh, Man! You may have saved me another fruitless attack. This is a great help Farm_Truck! Many thanks for the excellent pics and writeup. Rains are forecast foe me tonight and tomorrow so I'll have to wait for a break to try to duplicate your feat.


Will

Obvious labels in photos and file names. The end of the coat hanger was wet when I pulled it out after initial probing. The end of the borescope was also wet after going in for the close-up of the hole. Put water in with turkey baster after stirring the hole with the coat hanger and it came out the weep seam instead of filling the 'reservoir' until it cam out a hole near the bottom connectors. Good luck to everyone who gets this body hole plugged with junk -- the key is hearing the bubbling sound when blowing out the front sunroof drains. Water may slowly seep through the plug, but man, it flows so much faster when you clear that darn hole.

FT, with a small endoscopic device I already had, and looking through the holes vacated by the electrical blocks, I can see a hole in the side of the "reservoir" but see nothing on the floor of the cavity. Is this what you consider the escape route for the drained water? Mine seems to be filled with auto body seam filler. It's flexible and rebounds when I poke it with a coat hanger wire.

 

Ours is a 2008 Limited Hybrid -- not sure if that would make any difference or if body parts could have changed slightly. The hole was definitely in the bottom and I could feel the coat hanger drop as I slid it around. Did not notice any holes around the edges. Bottom would allow water to drain and not have some remain. Wouldn't really make sense for the passenger side to differ. ??????????

 

I have a related problem only it's higher up. Water is pouring out of the drivers side sun visor mounting/pivot bracket. Where are these drains located around the sunroof? All 4 corners, front corners, BOTH SIDES?

FYI - Weathertech floor liners installed today. I used a Bissel rug cleaner to suction out as much water as I could, then used a commercial vac at the car wash place. For the most part I held it down tightly and moved it around just where I could feel the damp. Since I can't leave the windows open I bought one of the household sized Damp-Rid buckets and it's inside now too.

My temporary fix? A window frame of shipping tape on the sunroof.

 

Think of this bottom section of the pillar as a can that has a hole on the bottom of it. The can sits over a section at the end of the weep seam -- sort of a double wall construction. If your vehicle has the rubber plugs along the length of the rocker panel that makes one side of the weep seam, just pop one of these out to see what I mean by double wall construction. There's just enough room to slide the 1/4 tubing in to blow some of the debris out of the seam. The seam also runs all the way from the front to the rear tire, so if one area plugs, water just flows to the next. Seems like an ideal area for future rust trouble.

I have a related problem only it's higher up. Water is pouring out of the drivers side sun visor mounting/pivot bracket. Where are these drains located around the sunroof? All 4 corners, front corners, BOTH SIDES?

Open the sunroof and stand on the driver's side threshold and look into the front corner of the sunroof. You should see a hole that is just over 1/4 inch diameter near the bottom of the front corner. There is one of these at all for corners of the sunroof -- essentially making a gutter system to drain the water that makes it past the leaky seal around the glass. The seal is leaky on purpose since the glass must move above the roofline when tilted open and move below the roofline when fully retracted. The rear drain holes are around where the back corner of the glass ends up in the fully open position -- impossible to see without and difficult to see with a borescope. Tubing connects to a hose barb on the back side of these holes top direct the water to the exit point from the body. Through the A pillars and to the weep seam for the fronts and through the C pillars and to an exit point directly behind the rear tires for the rears -- the tubing actually exits for the rears. Care must be taken to not damage or disloge this tubing. Thats the drainage system for the sunroof.

If water is coming out from your advisor attachment point, it may be overflowing due to a plugged drain hole or plugged tubing and running over the gutter and over the top of the headliner or possibly the tubing disconnected from the back of the drain hole. The slope that your vehicle is parked on should impact the amount of water going into the various drain holes.

Good luck.

 

Think of this bottom section of the pillar as a can that has a hole on the bottom of it. The can sits over a section at the end of the weep seam -- sort of a double wall construction. If your vehicle has the rubber plugs along the length of the rocker panel that makes one side of the weep seam, just pop one of these out to see what I mean by double wall construction. There's just enough room to slide the 1/4 tubing in to blow some of the debris out of the seam. The seam also runs all the way from the front to the rear tire, so if one area plugs, water just flows to the next. Seems like an ideal area for future rust trouble.

I concur with your assessment. At one point while searching under the car over the past few days, I pulled out a plug (about 1 1/2 inches diameter) located about two feet from the seams and toward the front of the car. Out gushed a volume of water that I had poured down the drain tube. I had mixed it with Simple Green, that detergent, thinking it would help flush the system, so knew where it came from. Certainly seems strange that non aerated cavities would be open to water intake and, as you note, a major inducement to rust.

 

You can do all these things but nothing really works well and it just happens again. This is what I did:

Pull up the driver's side carpet. Find the grommet back by the fuel door lever. Pull it out and pour some water through it. You should see water pouring out the bottom. This is your new drain!! Yay!!

Pull off the a-pillar cover. There is a little plastic hook you have to bend 90 degrees to remove the cover completely. This is the hardest part. Once off find the white drain hose.

Pull it out!! Yank that sucker out of the fender! Use a razor blade to cut it at a convenient spot. Take the hose to home Depot and find a hose that fits snugly inside the original hose. You'll find tubing in the plumbing department. 10 feet is plenty.

Take a wire or coat hanger and run it down behind the dash so it comes out in a good spot under the dash. Tape the tubing to the wire and fish it down.

Cut the grommet so it fits tightly around the tubing and make it so an inch or 2 sticks out. Put grommet back in hole.

Route tubing along side the wiring loom. A zip tie or 2 helps here.

Cut tubing to length and push as far into original drain tube as you can.

Pour water into sun roof drain and watch it flow!!! Woohoo!!!

Reassemble. Tell wife it took all day.

You're welcome.

 

I am certain that I have the same clog since I hear gargling when I blow air through one of my sunroof drain holes. Unlike the OP, my issue is on the passenger side, not drivers side. I am wondering how different the instructions are being that my issue is on the other side? Do I need to purchase an endoscopic in order to fix the clog? Thanks for any insight. Been dealing with this issue on and off for 2 years

 

I see that you followed my advice, Andrew, and came to the appropriate thread. My problem, like yours, was on the passenger side. I removed the plastic cover to expose the area, removed the electric connect box (didn't unplug anything) to make access to the water collection "box" and with my very basic endoscope took a look. I found that a mechanic's mirror - the kind on an extendable rod - was of more benefit than the endoscope. Any way, after using a little Dawn dishwashing detergent in the water "box" and stirring it and using a bit of compressed air and a suction the accumulated dirt/whatever loosened. I also used compressed air (at 150 psi) under the car to blow into the seam where water is supposed to drain from. Finally, the drain cleared and water now flows where it is supposed to. HTH

Will

 

This is a simpler solution that will last indefinitely:

 

This is a simpler solution that will last indefinitely

I went with this method because I was more comfortable doing it and I know the cowl drains will eventual clog up again. This method is very straight forward how the water exits the vehicle. Thanks for taking the time to make the video, I included a couple pictures to help assist anyone one else that may find this thread. Took about 20 minutes for a noob like myself.

...

 

Looks like it will work, OK, RB. Where does water drain from under the vehicle?

 

It drains out the floor by the gas door lever. Permanent and easy to clean out on the rare occasion it clogs again. All for under $10.

 

Another trick to discover where the water is collecting is to remove the kick panel and pour soapy water down the sunroof drain. The bubbles will tell the story! More than likely it is gathering in the dreaded hidden basin and you will have to clean it out like I did in this post:

Highlander sunroof drain problem

Floor mats in my highlander get soaking wet with every heavy rain. According to Toyota, my 2008 Highlander sunroof drain is routed through the door front pillar. The bottom end empties into a cup with a small drain hole in the lower frame. The drain hole is partially blocked resulting in...

www.toyotanation.com

 

I'm visiting and bumping this thread again (and I hope for the last time) to mention what I did that finally works. I followed RabidBeagle's route on both sides of the car and rerouted the drain tube to the outlet he detailed. I discovered four days ago after a deluge that then new drain would not flow the same volume of water (slightly smaller internal diameter) and wound up with water in the passenger side floor again. The car was parked on a slight incline, front down, and canted slightly to the right and the water thus flowed to that side and simply overflowed the tray and followed the outside of the drain tube and pooled in the psgr side floor.

After drying the carpet out again I saw that there is a very small gap between the front edge seal on the sunroof where water enters. I found in my stash some thin rubber roofing material about 2-3 mm thick and cut a strip maybe 10mm wide and used a silicone sealant to affix it to the front edge and about 5-6 inches on each side of the sunroof opening. After another heavy rain yesterday - no water in the floor and none in the tray. That strip probably would have fixed the problem in the first place. I'm hoping mightily that is the last time I need to address this issue.

Will

 

Hey Will (TN SkyPilot),

I did the same drain tube re-routing thru the grommets in the floor and it seemed to have worked (or so I thought). For a couple of weeks didn't feel any wet carpet after several normal rain events, but we had a huge deluge this past Friday and wouldn't you know it, water found it's way back into the passenger side again like your situation.
Would you have a photo of your fix of the front edge seal on the sunroof that you patched up with the roofing material and sealant ??

Also watched the video Andrew Warner linked to in post #24, so I'm also going to remove the rear bumper cover and check for any missing grommets behind the bumper cover as the rear passenger floor is also getting wet.

 

Here they are: installed and the material used.

 

Ok....I had some rubber weather-stripping already laying around the garage, so I put it in like TN-SkyPilot did. I also pulled the rear bumper cover as mention in the video linked in Andrew Warner's post. I found I had 2 out of 3 missing body hole plugs behind the bumper cover on the right side and 1 missing on the left side. Here's the video I followed to find the missing hole plugs.

So now waiting for the plugs to get shipped/delivered. I'm hoping that once I put everything back together this water leak issue will be resolved.

 

Sorry to revive an old thread, but I seem to be having this issue on my Lexus IS. Do you guys have any idea where the water is coming in from? Or did we determine that it was just coming in from the sunroof?

I poured water down the driver side sunroof drainage tube, and it drained out the bottom as quickly as I poured. With the driver side footwell being relatively dry, I didn't remove any of the panels though. The car's been in the garage for like a month, because after my last hand car wash, I'm assuming water got into the fuse box, and the car just starts and immediately dies after.

I've had the car for 2 years, and it's always been parked in the garage, and I never open the sunroof. I'm trying to figure out where the water is coming in from first before I take it to the dealer to diagnose the electrical problem.

 

I used weed eater line to unstop or open tube. The best, without too much trouble is pour a cheap (I used DG Brand 1 $) drain cleaner in a coke bottle in the channel wait 10 minutes and flush with warm water and watch it start draining!

We are definitely having a different issue, but I may also explore this one on my wife's vehicle just for future prevention.

Use drain cleaner then flush after 5 or 10 minutes with warm water. It.worked for me.

 

This is easy and it works.

I have an 07 Highlander with the sunroof. Drains from my sunroof were plugged up enough that water began pooling on the driver's side floor. I have a piece of acetyl plastic rod (Delrin is a trade name, this plastic is very tough, durable, and slippery, it's used for bearing material) which is 1/8" diameter x 8 feet long (part of materials I have for work). I opened the sunroof (slid it back) and standing outside I was able to find the top hole of the drain tube which runs down through the driver's front pillar (there's a drain on the passenger side too). The hole is in the driver's front corner of the gutter or trough which runs around the perimeter of the sunroof port in the roof to catch water and direct the water to the drains. Once I found the top hole of the drain using the end of the plastic rod, I pushed the flexible tough plastic rod down the drain tube as one would use a drain snake in household plumbing drains. About 6 1/2 feet of the 8 foot rod went down before I hit something which stopped the rod. I slid the rod in and out about 6" while twisting it (I envisioned the end flopping or thrashing around in the neighborhood of whatever was stopping it). Suddenly the gutter at the top cleared and water began running out from under the car indicating that the exit end of the drain had cleared. Hopefully this will stop the water from running out inside the car and soaking the carpet.

After I was finished, I tried to close the sunroof and it kept stopping and reversing rather than closing all of the way. I had bumped the foot end of a black coil spring off of it's footing. The top end of the coil spring was still secured in place. This footing must have a sensor which allows the roof to close all the way. There are two of these springs under a flap which moves up and down (when the roof is opening and closing). I think the flap is a wind deflector, and it has to be all the way down and out of the way for the sunroof glass to slide into place. The springs are right near the top hole of the front drains on either side under the flap. I was able to lift the foot of the coil spring back onto the black rubber cone shaped footing it normally rests on, and then the sunroof closed properly.

 

Has anyone on here experienced wet floors in the second row? I'm going to try a combination of these methods this afternoon (snaking with string trimmer line, blowing air up the drain lines from the bottom, and possibly replacing drain tubes, maybe even taking the rear bumper off to look for rubber grommets), as my son's 2008 Highlander has wet floors on BOTH sides, but we noticed that water is in the floor of the second row as well.

I will never buy another car with sunroof again.

 

It could be the rear sunroof drains or possibly the condensate drain from the rear AC. Last summer I was driving myself crazy because I had wet floors in front. I was cleaning sunroof drains and still had issues. Turned out it was the AC drain hose under the car. I guess now at least I know my sunroof drains are clean LOL. The rear sunroof drains exit just in front of the rear wheels IIRC and I don't know where the AC drain is. Never looked Though keep in mind the AC unit is on the pass side of the rear area. So, it may not be that at all since there are sunroof drains on both sides. Good luck they're a royal PIA to get to

 

This may help. Had same problem related to clogged front drains causing the rocker panel to fill up and drain from the pillar between the doors onto the rear floor.

https://www.toyotanation.com/threads/sunroof-drains-2013-highlander-a-question-with-how-to-video-links.1774956/#post-14956881

 

Currently having same issue on the front passenger seat