RX 300 water ingress

[Tomtit]

My wife's recently-acquired RX300 began to smell musty inside. Lifting the carpet revealed water in every footwell and in the rear of the car. Having read a number of helpful posts on this forum I decided to strip out the whole interior to find the source of the leak(s). I removed the headlining, the carpet and everything in between. I found that water was entering past the roof rail bolts and at the rear behind the bumper. I then removed the roof rails and rear bumper cover.

I bought some Tigerseal seam sealer and ran it under the roof rails where the seams join. I did the same on the vertical sections at the top where the tailgate sits. I put seam sealer behind the bumper cover and inside the car; it is light grey on the attached images. I put silicone sealant under the fixings for the tailgate struts and behind the black plastic parts shown on the image which are behind the bumper cover. Water was also getting in via the nearside rear wheelarch, as shown by the patch of rust on the inside of the car. There was a small area of exposed rusty metal under the wheelarch which I covered with underseal. I also put silicone sealant behind all the rear light units.

The car is now watertight and I can look forward to putting everything back together. I hope this post will help others who may be struggling to trace leaks.