I hate Toyota sunroofs

[Malleus]

So my 2008 LX570 decide not to start last Friday morning. After spending the required 15 minutes checking all the "obvious" causes, I gave it to the Lexus dealership, because
a) the US government kind of expects me to be there while they're paying me, and
b) I already have an 80 undergoing a head repair, and don't have the "extra" time to spare on this.

After two days of troubleshooting, I'm informed that the sunroof drains are "a little clogged" and "have been weeping into" the passenger side pocket behind the kickpanel that houses the fuel pump relay connection. The connector housings were both full of corrosion (I saw the photos), which prevented the terminals from doing their job.

Mind you, I've had this truck for 12 years and the sunroof has never leaked, no wet headliner, no wet carpet. Ever. It's been outside, not under cover for maybe two years of the 12 I've owned it. And yes, I keep it clean.

Just received notification that, upon further investigation, the entire harness, in both A-pillars, is corroded and Lexus wants to replace it.

Sit down for this: the service advisor's estimate, to replace the wiring harness (just the harness, not anything connected to it):

$12,627. US dollars, not pesos. or rupees. or rubles.

 

[bloc]

Sorry to hear about this.

Here's the thing.. if the gasket is in good shape the drains shouldn't clog. But due to UV exposure it shrinks, lets crap through, drains may clog..

Even worse, as the gasket shrinks it allows more water through than even clean drains can handle depending on if the vehicle is on an incline sending all the water to one drain.

I recently ordered a new sunroof gasket to try and refresh mine.. supposedly not available for LC without the whole panel, the LX has the gasket only available. I'll find out if it fits and post.

I'd consider a new gasket. 63251-12190 Double check whether it applies to your year.

As for the harness.... that kind of money justifies a solid go at repairing it. I doubt it's so corroded that you can't go in one by one with the correct parts and crimping tools and refresh the connector. But yeah, it will take a while. That kind of money also justifies a rental car for a while. AND, you won't have to trust a tech to install the entire dash and harness correctly.

 

[bloc]

This also brings to mind the idea of drilling the area and installing one of the one-way water drain grommets you see in some air boxes. That way any water that makes it into the area drains before it can cause any damage

 

[alwaysme]

sorry to hear that, noway I would pay that. Why not source the harness from a junk yard? or is the 12k mostly labor ?

 

[Malleus]

UPDATE:

It's not just the interior (dashboard) harness, it's the engine harness too. At least all the engine harness connections on the rear side of the firewall. And I'm told the corrosion has spread beyond the connector housings to the wiring behind the terminals, so it's not just a matter of disassembling the connector housings and cleaning them. No word yet on what damage has been done to every single component that's plugged into the harnesses.

From what I can tell, about $7,500 is harness(es); the rest is all labor. And yes, there is no way I'm paying that much for the job. I paid 4$k for it 12 years ago, when I bought it, with 40K on the odometer.

I'll do it, over many, many days, it's just the fact that this worthless sunroof can't seal well enough to prevent a failure of this magnitude, and that it could be acceptable to design one that would fail this way. This has been a perennial problem since Toyota put sunroofs in LandCruisers three decades ago.

 

[Leaky2014]

it's not if, it's when people, wake up!

if you haven't had this "issue" yet get some dielectric grease and coat the s*** out of those junction boxes and I do mean the inside where the connectors are or pay $12k
Seems this "issue" is appearing more and more often.
Dielectric grease is cheap, wiring harnesses are not.

 

[Leaky2014]

This also brings to mind the idea of drilling the area and installing one of the one-way water drain grommets you see in some air boxes. That way any water that makes it into the area drains before it can cause any damage

This won't work, at least not 100%, true most water will drain but any water that hits the connectors when power is running though them will corrode and continue to corrode after the water drains out.
You know what will protect them though.....

 

[Malleus]

This also brings to mind the idea of drilling the area and installing one of the one-way water drain grommets you see in some air boxes. That way any water that makes it into the area drains before it can cause any damage

This is the problem with the 80s, which is why the rocker panels rot out, but not the problem here. This problem is that it actually "rains" inside the kickpanel. The only 100% fix is welding the sunroof panel closed.

 

[Malleus]

it's not if, it's when people, wake up!

if you haven't had this "issue" yet get some dielectric grease and coat the s*** out of those junction boxes and I do mean the inside where the connectors are or pay $12k
Seems this "issue" is appearing more and more often.
Dielectric grease is cheap, wiring harnesses are not.

Toyota was supposed to have sealed these connectors, like the ones in the engine harnesses, which are constantly wet and don't corrode (unless sprayed liberally with coolant), so this can't happen.

I can see this on a Scion, or some other POS, but not on the Lexus flagship.

 

[Leaky2014]

Toyota was supposed to have sealed these connectors, like the ones in the engine harnesses, which are constantly wet and don't corrode (unless sprayed liberally with coolant), so this can't happen.

I can see this on a Scion, or some other POS, but not on the Lexus flagship.

These 100% should be watertight, however I can see Toyota point of view on this.
IF, and that's a huge ****in IF, things stayed the way they come from the factory these don't need to be water tight, however as I know and you know and at least one person on here finds out weekly ,that is not the case.
Luckily I came across this issue early, so mine are now well protected.
Mine came about after some douche at some s***ty body shop full of mouth breathers did some hail repair and decided it not necessary to connect this sunroof drains hoses.

 

[grinchy]

I'd consider a new gasket. 63251-12190

proud owner of a new gasket! have had one sunroof clog/leak already. need to nip this in the bud

 

[mobi-arc]

How about we quit buying vehicles where they cut a giant hole in an otherwise perfectly water-tight roof. The whole concept of sunroofs is so mind-numbingly dumb as they're guaranteed to leak and break....not if, when. My 80-series had no sunroof and I loved it. My 100 and 200....giant holes in the roof.....irritating as hell.

 

[brasskey]

Is there a post somewhere on cleaning out those drains? Seems like a good preventative measure to take every year or so.

 

[kwelhand]

Amazon product ASIN B097P89Z88
I use this sunroof drain cleaner to clean out all of our worthless sunroof on family vehicles.
Very flexible and w/ soft brush but works surprisingly well!

 

[bloc]

This won't work, at least not 100%, true most water will drain but any water that hits the connectors when power is running though them will corrode and continue to corrode after the water drains out.
You know what will protect them though.....

Right, because if they get a faint misting that dries in 20 minutes they'll turn to dust. After all that qualifies as "any" water.

Be careful speaking in absolutes.

I can't find a major auto manufacturer that uses dielectric grease, because it isn't necessary. Not even in toyota's procedures to repair harnesses and connectors, where saving a few pennies producing a million vehicles isn't a significant cost burden.. no mention of the stuff. It attracts dirt and makes future work on connectors vastly less convenient. The connector materials are designed from the beginning to handle the designed electrical loads, plus vibration, expansion/contraction from heat cycling, age, even some level of contamination. Sitting in a pool of water isn't what our interior wiring harnesses were designed for, and my bet is unless your magic grease was specifically designed for submersion, it would end up a disgusting mess with corroded terminals over a long enough timeline anyway. Note that dielectric grease manufacturers make special formulations for water exposure.

How about we quite buying vehicles where they cut a giant hole in an otherwise perfectly water-tight roof. The whole concept of sunroofs is so mind-numbingly dumb as they're guaranteed to leak and break....not if, when. My 80-series had no sunroof and I loved it. My 100 and 200....giant holes in the roof.....irritating as hell.

I agree completely.

Is there a post somewhere on cleaning out those drains? Seems like a good preventative measure to take every year or so.

Whatever you do don't use compressed air!

The rear drains are about impossible to get to anyway.. I try to keep the sunroof gasket and opening clean, and the parts of the tray I can easily get to, to minimize the crap that will make it to the drains.

 

[GordJ]

How about we quite buying vehicles where they cut a giant hole in an otherwise perfectly water-tight roof. The whole concept of sunroofs is so mind-numbingly dumb as they're guaranteed to leak and break....not if, when. My 80-series had no sunroof and I loved it. My 100 and 200....giant holes in the roof.....irritating as hell.

Do you feel the same way about windows? I‘ve had lots of sunroofs in 4Runners and Pathfinders and Muranos and Audis and even Blazers that didn’t leak but both the LC and the LX have leaked.
And I’m on the “dielectric grease is good” team.

 

[MTKID]

This is the problem with the 80s, which is why the rocker panels rot out, but not the problem here. This problem is that it actually "rains" inside the kickpanel. The only 100% fix is welding the sunroof panel closed.

I plan on eliminating (permanently having a fill panel welded over the hole after removing the sunroof mechanism) later this year. I’ve opened it maybe once in 5 years

Then a custom headliner, also eliminating my screen thing that isn’t used either.

 

[Leaky2014]

Right, because if they get a faint misting that dries in 20 minutes they'll turn to dust. After all that qualifies as "any" water.

Be careful speaking in absolutes.

I can't find a major auto manufacturer that uses dielectric grease, because it isn't necessary. Not even in toyota's procedures to repair harnesses and connectors, where saving a few pennies producing a million vehicles isn't a significant cost burden.. no mention of the stuff. It attracts dirt and makes future work on connectors vastly less convenient. The connector materials are designed from the beginning to handle the designed electrical loads, plus vibration, expansion/contraction from heat cycling, age, even some level of contamination. Sitting in a pool of water isn't what our interior wiring harnesses were designed for, and my bet is unless your magic grease was specifically designed for submersion, it would end up a disgusting mess with corroded terminals over a long enough timeline anyway. Note that dielectric grease manufacturers make special formulations for water exposure.

Let's be clear, I love that YOU don't use dielectric grease.

 

[KLF]

@bloc I respect your valuable contributions here, but I've been using dielectric grease for many years in many MANY applications, and I've never had any of the issues you mention.

Toyota also doesn't apply anti-sieze on any fasteners, but you better believe I use that stuff liberally. Every single bolt/nut that I can get a wrench on under my truck has been removed, greased, and reinstalled.

Back to bitching about sunroofs...

 

[bloc]

@bloc I respect your valuable contributions here, but I've been using dielectric grease for many years in many MANY applications, and I've never had any of the issues you mention.

Toyota also doesn't apply anti-sieze on any fasteners, but you better believe I use that stuff liberally. Every single bolt/nut that I can get a wrench on under my truck has been removed, greased, and reinstalled.

Back to bitching about sunroofs...

I’ve done a diesel swap into a 4runner (built the harness), three manual transmission swaps, LS swap into my 80 (built the harness), put a 97 fzj body onto a 94 frame and engine (shocking amount of wiring work), traced down a singe wire fault deep in the engine harness of a German car, and a few other things over a few decades of wrenching on cars.

I’ve never had a situation in which dielectric grease would help, but thousands of terminals where it would make diagnosing and addressing real issues more work.

As for anti-seize.. Toyota actually does put dry formulas on specific hardware, like our brake caliper bolts. On other things anti-seize changes the required torque values to achieve a specific clamping force.. all values are published assuming dry fasteners. Do you adjust your torque numbers?

Which isn’t to say it isn’t appropriate on certain fasteners on an old vehicle where the parts have already corroded.. but to stick it everywhere under the vehicle.. then again I have no clue how much salt they use in NH.

But yeah, sunroofs suck.