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pscan.eu

Well-Known Member

• Dec 9, 2024

• #1

The V6 that I took the auto gearbox and wiring loom from had a brass sensor (I guess temperature) inside the fuse box where the engine ECU lives, but the 1.8 doesn't have one.

Anyone know what it's for?

 

andyfreelandy

Well-Known Member

• Dec 9, 2024

• #2

Switches a fan on in the ECU case. Hadn't noticed it is not on the 1.8. The TD4 also has one.

 

Nodge68

Well-Known Member

• Dec 9, 2024

• #3

As Andy said. It's a 35°C thermostatic switch, which turns on the environmental box cooling fan.
From memory it's only the automatic gearbox models that have the cooling fan in the environmental box.

 

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pscan.eu

Well-Known Member

• Dec 9, 2024

• #4

ah, well mine is getting an automatic ECU, but I didn't know about the fans.
It probably doesn't get hot enough in the UK to be an issue

 

Alteredtech

Well-Known Member

• Dec 10, 2024

• #5

Hi,

I have a manual TD4 from 2004, there is a fan in the Environnemental box. I finaly understand why there is empty pipes going in the car from to that box, when I finaly find the fan.

 

Nodge68

Well-Known Member

• Dec 10, 2024

• #6

pscan.eu said:

ah, well mine is getting an automatic ECU, but I didn't know about the fans.
It probably doesn't get hot enough in the UK to be an issue

Click to expand...

The ECM in a sealed box will get hot enough to shut down, hence the cooled air supply from the heater intake trunking.

 

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pscan.eu

Well-Known Member

• Dec 10, 2024

• #7

it seems a bit elaborate when it's right next to the air box and they could have just pulled air on its way to the engine through the fuse box.

Anyway, I guess I can fit the fit later.

 

Nodge68

Well-Known Member

• Dec 11, 2024

• #8

pscan.eu said:

it seems a bit elaborate when it's right next to the air box and they could have just pulled air on its way to the engine through the fuse box.

Anyway, I guess I can fit the fit later.

Click to expand...

The ducting passes cool air from the heater intake plenum, and passes warmed air back to the heater intake plenum.
I suspect this was done to ensure only air can enter the environmental protection box, as water would be undesirable in there.