Rx400 Leaking Down C Pillar

Nigsy · January 7, 2016

I have been trying to trace a source of water collecting in the boot (trunk) of the car. I noticed water running down the inside of the trim near the tailgate hinge. (see photo) Anyone have any ideas how it is getting in there and how to address it?

ChrisKaye · January 7, 2016

Hmmm, I wonder if that could be a problem with the rear sunroof drain holes/tubes? I assume you have a sunroof?

The following image took a lot of digging up!!

Nigsy · January 8, 2016

Thanks Chris. I have found the two front drain holes and they are clear. I wasn't able to see the rear holes so your diagram will be helpful. Will have a look if it ever stops raining here.

Vicmeldrew · January 8, 2016

Have a read through http://www.lexusownersclub.co.uk/forum/topic/87267-water-ingress-rx400h-2006/ further down the page. There are a lot cases of water in boot and numerous solutions to the problem. I eventually stopped water in my boot but it took a lot of work and I'm not sure where it was actually getting in but it's still dry thankfully.

ChrisKaye · January 8, 2016

I can also think of another possibility - water from rear wash wipe may be leaking from the hose or join?

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Nigsy · January 8, 2016

Thank you for the replies. Have poured water in the sunroof drain holes and it exits under the car. Doesn't seem to be related to the rear wash wipe as water appears even when stationary. Will persevere.

stevet · January 8, 2016

They've been known to leak around where the gas struts fit to the body.

chesterman · January 8, 2016

I am sure I have read elsewhere on this forum of at least one member who experienced a leak through the rear fixing point of the roof rails. His solution, as I recall, was removal, clean, renew gasket & sealant. Hope that helps.

Nigsy · January 9, 2016

Thank you for all the suggestions. The leak appears to be coming from near the rear roof rail support where the seam joins. Have sealed with silicon. We'll have to see how it goes.

Verbout · August 3, 2016

On 8 January 2016 at 9:50 PM, chesterman said:

I am sure I have read elsewhere on this forum of at least one member who experienced a leak through the rear fixing point of the roof rails. His solution, as I recall, was removal, clean, renew gasket & sealant. Hope that helps.

We had this exact problem with our Vectra roof rail system.

The clips under the cosmetic roof strip are held in place by rivets that come loose allowing water to run down the c pillar.

We drilled the rivets out, tapped the holes and put in small bolts covered in sealant.

Job jobbed.

PCM · August 4, 2016

On 1/7/2016 at 11:29 PM, ChrisKaye said:

Hmmm, I wonder if that could be a problem with the rear sunroof drain holes/tubes? I assume you have a sunroof?

The following image took a lot of digging up!!

Sorry - re quoted because it's just such a good resource to print off and keep with one's Lexus documentation...

Verbout · August 4, 2016

Like that idea Piers, printing off for future references

I save some snippets as PDFs and save links to other information.

some of the how to's on changing spark plugs and brakes are excellent.

ChrisKaye · August 12, 2016

I think we all squirrel good info, there have been some great posts and book marking links to websites is not enough as I have often found the website has disappeared when I need the info the most! [emoji52]

Mooismum · July 18, 2019

Hi I've water ingress which has resulted in the hybrid system being affected, I've sorted that out know but need to remove the c pillar in the tailgate to seal the steam where the water is getting in. How do I do this please?