Smoke comes from the dash!

[alphadeltaromeo]

Here's the problem that I've identified. I was driving the car yesterday when all of a sudden, smoke started coming from the dash. First slowly and then quite a bit more came out. I pulled over quickly and shut it down. Popped the hood and saw smoke from the mono-valve (I think it's a mono and not duo, but not sure). Anyway, there was water at the base of it.

This is a 95 E300D.

The other thing that happened is now, even if the air/heat control is set to the off position, it won't turn off and will cycle high and low fan randomly. Cold out of the center vents and hot from the sides.

I believe it's the mono-valve, but there are two cylinder looking things and it's the one closest to the battery that appears to be leaking, as there is fluid at the base. The two cylinders sit next to each other.

Can I get some input as to over all thoughts on repair?

Much appreciated,

Andy

[Diesel911]

I do not know enough about your year of vehicle to comment for sure. But, on my 84 300D the Auxiliary Water Pump (electric) does not come from Mercedes with a Fuse in the Circuit.
When it shorts it has actually cause under the Dash Fires when it burns part of the Climate Control.

[alphadeltaromeo]

So it's the one of the left like I commented. Is that the mono-valve? What's the the cylinder on the right?

I'll check the fuse, thanks for the input...hadn't thought about that.

[alphadeltaromeo]

I will add that because of the tight spot it's in, I didn't have lots of visibility, but with that said, it looked like it was leaking from the left pod, but I'm not completely certain.

[alphadeltaromeo]

So I'm trying to source the mono (duo) valve right now...but I may have toasted the ac/heat control system. Like I mentioned in the first of the thread, the unit keeps the fan on full time. If I have in fact damaged the control system, if it's disconnected (until I can source a replacement), will that prevent me from driving the vehicle? Can it damage anything on the ac/heater system?

[connerm]

Valve is toast. Klima relay may be toast, CCU is probably toast. The valve will cost you plenty. Was the smoke from burning plastic or burning coolant? Where exactly was the smoke coming from? top vents? CCU?

I replaced the valve on my 95 a while ago. It wasn't that much fun. I posted a thread related to the job.

[alphadeltaromeo]

$400+ just for valve/pump assembly. I may find one in a parts yard.

The smoke was definitely coming from the CCU (coming out from each of the switches, front vents and looked like it was coming from the mono-valve area, but it was windy and getting dark unfortunately. Smoke smelled like burning brakes to start and then electronics-fried smell.

Where is the Klima relay and what is it?

[alphadeltaromeo]

Can I just disconnect the entire CCU and drive it without issue?

[alphadeltaromeo]

Any thoughts? Can I just disco the unit and drive without issue?

[alphadeltaromeo]

I've taken the CCU out and it's quite melted. So does anyone have a parts car with a CCU? I'm also looking to source a used monovalve/pump assembly. I'll check the parts places as well.

Thanks,

Andy

[alphadeltaromeo]

Well...it's confirmed, the unit is toast.

[compress ignite]

you disconnect ALL the POWER to the HVAC system ,no problem driving it.
BUT,You're gonna get frostbite sometime between November 2010 and March
2011.

Lots of ReCyclers in the Metro area (Gotta be, with 4.5 Million souls on Board.)

[alphadeltaromeo]

I pulled the CCU and the power leads to the monovalve and pump. I'm driving without issue at this point, apart from the slight smell of melted plastic. Interestingly enough I'm getting warm air from the side vents, which would indicate water flow through the heater core. I should have some heat, although not much as the fan isn't connected.

I'm searching for parts