radiator fans berlingo van 2002

[berlingo2002]

Hello guys
please Be gentle its my first post,
firstly I have gone through the posts to see if I could sort this out without bothering anyone.

This is for an old lady that im trying to help as she really cant afford to take it to a mechanic and I realky want to help her

she noticed the other day the temp gauge went higher than usual.

I took it for a drive and these are the symptoms

I stopped the car and noticed that the fans came on but realy slow.

So the came on so im guesing its not the temp sensor with the 2 wires , just I bought one brand new and replaced it anyway But still same problem.

I then started the car and unplugged that sensor and the fanS came on full speed and a warning light came up on the dash and guage went full
so I guess the fans are ok aswell.

I also checked the other sensor under the temp sensor, the one with one wire but contection seemed fine.
I unplugged that sensor with one wire but nothing happened but when I earthed the wire the fans went full speed but the guage was showing 3/4 hot so to me it sounds like a sensor for critical overheat.

I also checked the 3 reLays and the seem to be clicking so I guess they are ok.

I haVe heard that there is 2 speeds and im guessing its the 2 speed not working.

please help

[Gadgetman]

Which engine does it have, and is a car with or without AC?

[berlingo2002]

Hi there
thankyou for your reply

Its a berlingo 2002 1.4 ltre with aircon

Cheers

[Gadgetman]

A 1.4?

The first I would have checked is if it has been bled properly...
(You need to jack up the front lefthand corner to get all the air out of the system on that engine)
Also, check that the radiator cap is tight.
While engine is cold, squeeze on the top radiator hose. If you hear wheezing from the cap, it's caput.
(There's a pressure valve in the cap that opens at 1.4Bar. This valve can fail... )

[berlingo2002]

A 1.4?

The first I would have checked is if it has been bled properly...
(You need to jack up the front lefthand corner to get all the air out of the system on that engine)
Also, check that the radiator cap is tight.
While engine is cold, squeeze on the top radiator hose. If you hear wheezing from the cap, it's caput.
(There's a pressure valve in the cap that opens at 1.4Bar. This valve can fail... )

Thankyou Ok I will check that tomorrow,

Yes Its a 1.4 litre van Australia delivered

Just a question , why would the radiator not bleed properly affect the fans not coming on full speed?

Cheers

[Gadgetman]

It shouldn't...

The fan isn't supposed to run all the time, though. Frankly, it rarely runs at all in my car here in Norway. Even in the summer...
(Contrary to belief, we do have summer here, too)

Bleeding and all that is just so that we can exclude variables.

Anyway, that's an AC model. That means the fan isn't controlled directly by the thermoswitch, but by the AC control system.

[berlingo2002]

Hi
Ok so I checked and the system is bleed correctly

Is there something that turns on the high speed fans

[brodfather11]

The sensor with the one wire that you earthed in the first post is the one which if the coolant gets too hot it turns on the high speed fans as you found out yourself.

I tested one in a 1.4 petrol and it was over 100% C before it worked. It doesn't contact the coolant , it sits in a dry pocket.
Is the thermostat working properly and radiator is not blocking up.

Apart from the gauge showing high what is the problem ?

[berlingo2002]

The sensor with the one wire that you earthed in the first post is the one which if the coolant gets too hot it turns on the high speed fans as you found out yourself.

I tested one in a 1.4 petrol and it was over  100% C  before it worked.  It doesn't contact the coolant , it sits in a dry pocket.
Is the thermostat working properly and radiator is not blocking up.  

Apart from the gauge showing high what is the problem ?

Hi there thank you for your time

Radiator is really good and very clean.
funny you mentioned thermosat I changed it today,
the gauge is fine and the temp climbs slowly as it should.

if I turn on the aircon the fans work fine.
but without the aircon and driving in slight traffic it gets 3/4 hot.

I know this car well asi have borrowed it from this lady for years and it only got to half way on the gauge

To me it seems like when it starts to get hot the fans come on but They spin very slow to the point I can stop them with my hand.

But with the aircon on they soin very fast

Cheers

[Gadgetman]

Do you have a chance to mesaure the voltage across the fan when it's running slowly?

I'm betting that it's lower than when running fast. Much lower...
There may be a ground fault or a failed fuse so the fan is instead drawing power through another component.