Starting this thread with a very deep breath...

So the cat had a surprise for me this morning when I got out of the house... the fans were on (no, the car was NOT on) and were quite noisy (like in a hot summer day). As soon as I opened the door, the fans shut off.
Turn on the car and it gives me 2 errors codes: P0850 and P0687.

Looking for the codes it seems to be mostly electrical related. The gremlins got a hold of her again...
Any ideas what might trigger this weird behaviour?

Last night it was quite windy and snow was blowing all over the place... no idea if this might affect the car in any way...

 

So I guess no one found their car with the fans on even though their engine was off over night?

Any ideas what might trigger the fans to turn on like that?

Hasn't happened again since then... But I'm afraid that if it happens again and stays for too long on, battery will be completely depleted and then I am starnded...

 

I suppose someone has to ask: which fan(s)?

 

The fans inside the engine bay, in front of the engine - the cooling fans...

 

Hey guys - reviving this because it happened again!

After returning to the car from work, I have found the engine fans on again on the car - car was off, and it has been off for 7+ hours; yet somehow the fans seems to start by themselves.

What I have noticed is that this happens usually when there is a lot of rain or very windy snow...
And both times it has triggered these error codes: P0850 and P0687. I don't know if these codes are on because the battery was used by the fans and is low... but that will be my guess.

I am very puzzled and concerned to be honest...
Any idea what rain could short in order to start the engine fans!? Is this even normal for this car... for the fans to start by them self!?

 

Car electronics can work in very weird ways, primarily because it has a common ground throughout the chassis, meaning things can ground out through ways you're not expecting, powering up things that shouldn't be powered up, and cause unexpected behavior.

There has to be water ingress somewhere that's shorting out connectors that aren't supposed to be shorted out. I'd be looking at the possible ways water is getting into the car: around the windshields, trunk lid, hood. Maybe drainage channels from the sunroof. Once you find where the water is getting in, you can trace the water to narrow down your search. I don't think codes are going to help you here - water likely is getting in somewhere and shorting out something that isn't supposed to be shorted - so codes may not relate at all to what's actually happening.

 

The codes may help - did you troubleshoot what they indicate?

I'd be checking/changing relays, checking circuits for any commonality and so on.

 

I completely agree... water somehow is finding its way somewhere somehow and its shorting things out.
I've been slowly searching and trying to find any possible leaks and so far all I know the trunk is always dry, interior is dry as well (floors and all that).

Regarding the sunroof, what will be the signs of a clogged drain?
I know each manufacturer likes to do things differently. All I can say by just looking around at the sunroof, it is sealing very well and never had an issue so far with water inside the car.

After you mentioned the windshield I looked at it to see if everything is in order and the only thing that I have noticed is that the lower part plastics don't seems to connect properly (first time I noticed this, never really paid attention to this).
What is under this thing and if water gets trough there, what kind of wires are under it?



In this case, the these codes are referring to Powertrain issue - and they can be triggered by shorts on the wire as well. Or faulty relays - I guess I could have a look at that if anything, just have to figure out where the relay is for the powertrain in these cars. They can also be triggered by low battery (which might be since the fans run on the battery without the engine on).

However, I highly doubt this is the actual issue and chasing to solve this might end up in wasted time. The codes clear themselves after 2-3 days of driving (and no heavy rain or windy, snow conditions).
But I would look at this as well, just to make sure... just have to figure out where are these relays.

 

I'm not a betting man, but that's where I'd start my search. If you look, the plastic windshield trim on the passenger side is not sealing against the windshield.

The ECU and main harness connections sit under here - if you pull this panel up which you can do without removing wiper arms, then check around the cabin air intake area in the corner. At the very least, check the rear-left corner of the engine bay for signs of water ingress.

 

Thanks Dave!
I will have a look at it over the weekend... Just the ECU and main harness? Nothing important I guess (sarcasm)...

Why they didn't bother to put this in properly is beyond me. Whoever worked on this car did a complete half *** job on everything they touched.

 

Well, I had a look at these trim pieces and it loos like they need replacement. The driver's side seems to be actually glued to the window ... and the passenger one just sits there, un-clipped (nothing seems to clip on) and the lip that is under it, and will sit against the window, is kind of broken and barely holding on. Can't make it stay in place as it needs to be. Its only hold in place by the trim clips (which btw were missing and I used something that I had around - have to find the OEM ones - they used zip ties).

One thing that bothered me and unfortunately I didn't got a picture of...

On the passenger side, around the ECU, there is a big round hole and behind it something that looks to me to be an air filter!?
Is there suppose to be a cover on this hole? It looks like water gathers behind this round hole just before the filter (there's like a small "room" behind this hole, just before the filter).

Is this where the air filter for the car sits? I thought this was replaced from the cabin, not engine bay.

 

Yep, the cabin/pollen filter is in the cabin not the engine bay. On a RHD model like my old XFS and XFR it is on the LHS under the glove box, so I suspect it's also under the glove box on a LHD car. To check pull the felty under panel off (called the "hush panel", just pull the three or four rectangular clips out across the front) and have a looksee underneath, you should see a rectangular slot that has a cover/lid which unclips and swings open so you can pull the old filter element out and chuck another one in.
Can't help you with the big round hole near the ECU!

 

AHA.

This is almost certainly your problem. Sadly I can't get a picture of my own engine bay at the moment as I'm working on the hood, but there is supposed to be a cover over that hole, and if you don't fit it, water WILL leak into the cabin. I had this happen when I hadn't fitted the cover back.

That hole is the air intake for the cabin, so if you look inside you can see the cabin air filter. You are correct that this is changed from inside the car, but it draws its air from the area around the ECU. The hole is supposed to have a plastic cover that is head in place by two (from memory) 6mm nuts - when this cover is fitted the water from the windshield runs either side of the hole but when it's not water can get inside the car through this hole.

You can see this cover illustrated in the Workshop Manual Section for removing the R/H Secondary Bulkhead Panel:

If yours is missing the part number for this panel is C2D5394 and the part number for the nuts that hold it on is C2C22722. The OEM Trim Clips for the windscreen finisher panel are XR87508, of which you need 7. The 8th hole gets filled by one of the 3 clips that hold the fuse box cover on.

 

@davetibbs - thank you for that!!!!

That is the spot and yes, that cover is missing from my car . Funny enough, the nuts are in place - and this is what made me wonder originally what were those nuts suppose to hold in place.

Thank you for the part numbers - I will start looking for them online and see where I can find them.
So far I cannot find this part number anywhere online - C2D5394.

In the meantime I have to figure out what to use to cove that thing up. I assume there is the need for some vents in order to leave the air flow in.

At this point in time I wish I can meet the person that touched this car and punch its face!

 

Sorry, I realized I didn't check if yours was a LHD US model but I can find that part here. Let me know if your car might be different.

 

Since it doesn't show any diagram, I am not sure if this is the part.
I'll shoot an email to the guys where I got my chains for the car and ask for their help. And I will use your picture in trying to explain them what part I need.

Not sure what LHD US means... I am in Canada, if that means anything.

 

LHD = Left Hand Drive = Steering Wheel on left side of the car.

In Canada that's the part you'll need. Here's a picture of it from an EPC parts site:

 

OH, lol, no idea how I didn't made the connection for the LHD .
Thanks for this as well - I've already sent an email to the dealer. Should have a new part installed soon enough - and hopefully this will stop my issues.

 

I'd definitely have a final check even once the leak is fixed to make sure where the water has got in hasn't gone all crusty when it hit electrical contacts. I'd focus on the fusebox in the passenger kick panel - have a good look around there for any signs of water ingress, pull a couple of fuses to check etc, just to make sure. Then once the panel is fitted you'll be good I reckon.

 

Since it looked soaked in water a little I am planning to change the cabin air filter as well, once I install the missing part, so I will be under the dash checking things for sure.

Good idea on the fuse box - I will have a look at it again just to make sure things are still OK.
I have replaced the windshield washer pump at the end of January because of the "wire water ingress" issue - cleaned the fuse box then and it didn't seem to be any other leaks at that time.