Coolant leak from unknown component

[lex - eleven]

Morning all. My car passed it's test today with an advisory of a coolant leak. The tester told me that he doesn't know what the component is and its a little hard to see with the lower covers in place. It's beneath the engine a little way back from the alternator and can only be described as a round disc or plate with a couple of bolts. Unfortunately I don't have a picture but was hoping I might get an answer or suggestion on here. He can't book me in for a couple of weeks so I'll top the rad up with coolant when it needs it until it's done. 

[lex - eleven]

I've been trying to find the component and believe it may be a freeze plug which is silicone and bolted on. I'll try sending the pic to the garage tester and see what he says

[BigBoomer]

11492-20010 PLATE, WATER SEAL
You'll have to order it from a Lexus/Toyota dealer.
Looks like this (this engine is upside-down!)

[lex - eleven]

Yes that looks like the kiddie. Isn't it just a case of removing the plate, re-siliconing it and bolting back on?

[Razor61]

looks like someone else has had the same issue

https://www.lexusownersclub.co.uk/forum/topic/127966-ls430-coolant-leak/

[Jaystar77]

Literally did this yesterday on my old RX300.

 

I just drained the system, unbolted it, cleaned/dried everything, fresh silicone applied then bolted it back up.

Left it overnight before filling the system again just to be safe but all seems good.