Tony Sestito
Tony Sestito PowerDork
11/12/20 7:10 p.m.

This week, I learned something the hard way, and wanted to pass it on to the GRM Hive. You may already know where I'm going. 

My parents have a 2014 Infiniti Q60 AWD, also known as a G35/G37 Coupe. Early on in the week, while on the phone with my parents, they mentioned their Infiniti has been doing some weird E36 M3. Namely, the dash lights would go on and off, the GPS system would shut off while driving, the car would start chugging while driving, lights would stay on and discharge the battery, and more. They also told me there's a water leak on the passenger side... interesting. This car has low miles and my mom is the primary driver, and she barely drives. 

They took it to the dealer, and they determined that the sunroof drain got clogged, backed up, and leaked water all over the BCM and associated wiring. The drain tube, located under the A-pillar, flows into a grommet behind the dash on the passenger side firewall. When these get clogged, they leak water all over the place. And the BCM is right underneath it under the kick panel.  

Apparently, this happens a lot with these. This is the culprit:

This $13 grommet has a tiny plastic baffle that gets clogged up with debris, and the result is a wet carpet at best, or thousands of dollars in repairs at worst, just like my parents' car has incurred. Why car designers put sensitive computers that control everything under places where water flows is beyond my comprehension. 

So yeah, if you own one, or you are thinking about buying one, CHECK THE DRAIN!!!

John Welsh (Moderate Supporter)
John Welsh (Moderate Supporter) Mod Squad
11/12/20 7:15 p.m.

Being a victim of weather (rain), I wonder if this could be an insurance claim? 

Tony Sestito
Tony Sestito PowerDork
11/12/20 7:21 p.m.

In reply to John Welsh (Moderate Supporter) :

They already traded it in. As soon as they got the diagnosis, that was the end.

And of course, they got another one, this time, it's a current-gen 2019 with the 3.0 twin turbo. I advised them to look at other stuff, but there aren't many non-German AWD coupes out there these days; it was this, a Lexus RC, or a Challenger GT. My mom loved the old one, so she wanted another one. Hopefully they redesigned the stupid sunroof drain. 

02Pilot UltraDork
11/12/20 7:21 p.m.

My father discovered the hard way that VW Golf Alltracks suffer from a similar problem. Warranties are very useful things, it turns out.

pointofdeparture GRM+ Memberand UltimaDork
11/12/20 7:35 p.m.

This is also a common problem on late model P1 chassis Volvos.

Tony Sestito
Tony Sestito PowerDork
11/12/20 8:33 p.m.

To quote my good friend Greg: "Sunroofs are the devil." 

dxman92 Dork
11/12/20 10:25 p.m.

I've owned one sunroof and never again.

NickD UltimaDork
11/13/20 7:36 a.m.

Sunroofs suck. Mine was the cause of most of the electrical issues on my '90 Acura Legend, I'm certain of it. I'll never own another sunroof car again.

noddaz GRM+ Memberand UltraDork
11/13/20 7:56 a.m.

I think anything with a sunroof can have clogged drains.  As far as "Why car designers put sensitive computers that control everything under places where water flows is beyond my comprehension. " where else are the designers going to put them?  The current cars are full of computers.

GhiaMonster Reader
11/13/20 8:39 a.m.

Put older Honda Accords on the list of cars with terrible sunroof drain designs.  Probably the same as the Infiniti, there is a grommet the drain connects to.  Apparently the drain tube shrinks as it ages and pulls out, draining under the dash onto the floorboards.  Fix for me was a piece of camelbak tubing spliced in place and several hours of mold cleanup.  Sunroofs are the devil. 

Also lost a Audi URS4 to plugged cowl vents filling the floorboards with rainwater, where the ECM lived.  ECMs should be mounted where the sunroof would be.  

In reply to noddaz :

It's not just the new cars.

I had a 85 BMW 635csi. 

Guess where the leak in that car dumped. 

Right in the back of the ECU. All they would have had to do to stop that from ever happening is turn the ECU over. It would have shed water instead of holding it. 


Tony Sestito
Tony Sestito PowerDork
11/13/20 8:54 a.m.

In reply to noddaz :

There are plenty of cars that put them under the center of the dash ahead of the shifter and in other places where it's less likely to get wet. This still isn't the worst place I've seen one; that prize goes to the 2007-10ish Hyundai Elantra. They put the BCM right under the cupholder. If anything, put them in a protective sleeve or something! At least Hyundai acknowledged their dumb design and performed a recall that added a protective cover over the harness and BCM.

Tony Sestito
Tony Sestito PowerDork
11/15/20 8:12 p.m.

My parents were supposed to pick up their new car yesterday. They ended up not buying it (the car had a previously undisclosed accident) so I offered to at least clean the drain for now so it stops leaking. Turns out that it was the driver's side drain, not the passenger side. What got wet over there? Well, the fuse box for one! Not ideal. 

Anyway, I snapped a couple pics:

This is a terrible potato pic, but the offending drain is that yellowed piece of plastic all the way in the back. As I moved it around, water was coming out of it and dripping to the floor. It hasn't rained in days here. Also, the foor is wet. VERY wet. 

And here's the grommet/nipple/drain thingy. As you can see, it was plugged solid with all sorts of gunk. That little baffle on the back is the problem. Once a little dirt gets stuck there, it blocks it right up. I ended up snipping that out so it flows right through. The tube wasn't much better' it was clogged up pretty good, but between a long screwdriver and some compressed air, I was able to get it clean. I put it all back together and checked for leaks, and there were none. 

Next weekend, I'll do the other side. I also asked my dad to pick up a small dehumidifier and stick it in there as soon as he gets it. Again, check your drains! 

BlueInGreen - Jon (Forum Supporter)
BlueInGreen - Jon (Forum Supporter) UltraDork
11/15/20 8:36 p.m.

I wonder if this is why a local car wash has a sign that says "Nissan sunroofs: use wash at own risk" or something along those lines.

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