Do Not Sell My Personal Information Jump to content


Heater matrix leaking


Recommended Posts

Driving home from work and I could here water trickling, got home and could see water in the passenger footwell mat.

pulled everything back and I can see water dripping in two separate areas from the heater matrix under the dash

lexus had this for a recall a few months back for the airbag, could they of damaged it? 

The higher I have the fans on the more it drips

Whats my options? 

Link to comment
Share on other sites


Right after doing a bit more reading I think I might have the common blocked AC drain. 

The water dripping is clear, there’s a slight damp feeling under the drivers seat as well, I’ve had the ac on a lot lately and the cooled seats 

Link to comment
Share on other sites

From what I've read, the blocked AC drain issue only causes water behind the front seat footwell and not under the dash. You mentioned that water is trickling under the dashboard so I'm thinking it may not be the blocked AC drain issue. 

But then you mention that the water is clear. If it's clear and not sticky and sweet smelling then it's unlikely to he coolant. There isn't really any other water in the car other than the AC water. Unless your car has clear water filled up instead of pink coolant. No chance of it being rain leaking in somehow? But you mentioned that you've had ac on cold so in which case I doubt it's been raining lol.

Link to comment
Share on other sites

2 hours ago, james250 said:

From what I've read, the blocked AC drain issue only causes water behind the front seat footwell and not under the dash. You mentioned that water is trickling under the dashboard so I'm thinking it may not be the blocked AC drain issue. 

But then you mention that the water is clear. If it's clear and not sticky and sweet smelling then it's unlikely to he coolant. There isn't really any other water in the car other than the AC water. Unless your car has clear water filled up instead of pink coolant. No chance of it being rain leaking in somehow? But you mentioned that you've had ac on cold so in which case I doubt it's been raining lol.

My coolant is definitely pink, the water is totally clear and not sticky or anything. 

Theres like a big long square ish plastic tube under the dash with water running through it and it’s coming from that. 

Theres slight damp under the drivers seat. 

It was raining really bad yesterday but I don’t think it was that 

Link to comment
Share on other sites


That is the oulet from the blower (fan) unit. There shouldn't be any water there at all. I'd suggest that you have a blockage in the scuttle area which has caused heavy rain water to build up in the scuttle area and overflow into the air intake. Look for a pile of leaves!

  • Like 1
Link to comment
Share on other sites

4 minutes ago, johnatg said:

That is the oulet from the blower (fan) unit. There shouldn't be any water there at all. I'd suggest that you have a blockage in the scuttle area which has caused heavy rain water to build up in the scuttle area and overflow into the air intake. Look for a pile of leaves!

That square tube is absolutely full of water so could it of got in there? 

Link to comment
Share on other sites

1 hour ago, steve2006 said:

Not sure if the IS is similar but on my LS there are drain holes next to the wiper arm spindles. If these get clogged the water collects then overflows into the air intakes.

Definitely sounds like what’s happened to me! 

Mir absolutely chucked it down while I was at work and flooded everywhere, so there would have been a lot of water hitting my car so would explain it 

Link to comment
Share on other sites


If it is a leaking heat element there should be a sweet kind of smell from the coolant in it. Have had that in another car several years ago and when circulating the air to clean the windshield it would be like an oily film on it.

The smell is not nice.

Link to comment
Share on other sites

6 minutes ago, Las Palmas said:

If it is a leaking heat element there should be a sweet kind of smell from the coolant in it. Have had that in another car several years ago and when circulating the air to clean the windshield it would be like an oily film on it.

The smell is not nice.

There’s definitely no smell or oil feel to the water

Link to comment
Share on other sites

Drove to work and back with heater on  full wack today, it’s got rid of all the water and everything is dry again! 

I’ll try and get the scuttle off tomorrow to have a look and clean it out. 

 

Thanks for for your help guys👍

Link to comment
Share on other sites

Guest bigbullhead
On 10/1/2021 at 9:21 AM, Matt1280 said:

That square tube is absolutely full of water so could it of got in there? 

I always pressure scuttle drain holes every time I wash my car as a lot of cars get blocked and the water finds ways of getting into the car

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share



×
×
  • Create New...