Berlingo 2.0 hdi cooling fan operation

[Raul]

Hello

The car is from 2003 and has an air conditioner. The problem is that the fan does not kick in with low speed. It kicks in when the temperature of the coolant is well over 100 degrees. I do not want to blow the head gasket.

I got a lexia tool to help to sort things out. I removed the front bumper two check the wiring of the cooling fan. I found there are two resistors- one is 0,54 ohm and the other is 0.8 ohm. Turns out that atleast the 0.54 ohm resistor is faulty because when I bridged it the fan kicks in with full speed when testing with lexia. I then switched it with the other - 0.8 ohm- resistor and it started to run low speed while testing and also switched to high speed when testing the high speed operation.
The question is - what does the 0.8 ohm resistor do? The fan seems to work even if the resistor is not in place. Is it for air con?

[wheeler]

Without looking a a specific diagram for your vehicle the injection ecu normally controls the high & low speeds but the BSI controls the mid speed for the A/C. They can use the resistors together or on their own to achieve the different speeds.

[Raul]

Without looking a a specific diagram for your vehicle the injection ecu normally controls the high & low speeds but the BSI controls the mid speed for the A/C. They can use the resistors together or on their own to achieve the different speeds.

Ok, that is clear now. Another question , just for information - what is the purpose of the diode like thing on the resistor. As much as I understand it is not in the circuit. The socket on the resistor has 3 poles but only 2 wires come into the resistor, so it seems it hangs there without doing anything.

[wheeler]

Its not a diode its a thermal fuse.

https://www.swe-check.com.au/editorials ... _fuses.php