o guys!
Need help again regarding radiator fan. How to keep it running all the time when engine starts?
Car in question is fiat punto 1.2i non ac(188a400), car heats up on traffic lights but remains fine on motorways.
I tried bridging the temprature switch wire which is near battery, nothing happened, but fan start working when i switch OFF the engine.

You are trying to address an effect instead of the cause.

If it is running too hot at slow speeds, that needs to be diagnosed and fixed. Running the fan is not fixing the problem, only hiding it.

First, check coolant level, and ensure the system is bled.

Second thing to check is the thermostat. From cold, cold not warm, start the engine and as it warms, feel the hose from the thermostat. It should remain cool for some time, then suddenly get warm as the stat opens. Keep hands away from moving components. Feel the hose away from the engine, as some heat will transfer along the hose. If stat is stuck shut, it will take too long for it to allow heat along the hose.

Next, the radiator. Once the stat opens, the rad should get hot all across, and gently the heat should travel down, without any cooler areas. Keep hands away from the fan and exhaust. If radiator is blocked, heat will not be lost properly. Check the radiator is not blocked with leaves or other debris.

Chali said:

o guys!
Need help again regarding radiator fan. How to keep it running all the time when engine starts?
Car in question is fiat punto 1.2i non ac(188a400), car heats up on traffic lights but remains fine on motorways.
I tried bridging the temprature switch wire which is near battery, nothing happened, but fan start working when i switch OFF the engine.

Click to expand...

Thats an OLD car now

So cooling system is going to be 'tired'

Radiator is prime candidate.. cheap and simple on a mk2

Dors it have a temp. Gauge.. or just a light?

I'm going to say again what pb has posted, make sure system is full of coolant not air.

I can't find the link to how to do the air bleeding but just because the coolant level in the tank on side of radiator is correct doesn't mean the radiator or engine is not full of air.

Yes we want to drive till it lasts ,not in favour of spending money on it.

Chali said:

Yes we want to drive till it lasts ,not in favour of spending money on it.

Click to expand...

I understand but you may need to spend a little bit, that is cheaper than replacing it.
Check there is no air where it should not be first, it is very easy and costs nothing.

Charlie asked does car have a temperature gauge or just a light that comes on when it's too hot?

Undo the radiator hose clip

Remove radiator hose from lowest radiator pipe

Catch coolant in a bowl

Undo the bleed screws 2 complete turns

COFFEE BREAK


look at the coolant in the bowl

has it separated.. ? 2 obvious levels ??

(That..along with the rust and dirt in the bottom of the bowl.. are contaminants)

If its all clean and good (no filtration required )

You can :

Refit lower hose

Tighten hose clip

Refill radiator (when less than 0.5 litres left in bowl.. check for dribbling from the bleed screws)

Slowly add remainder of fluid..
Watching for fluid appearing at bleed screws.. tighten closed when fluid appears

Add remainder of coolant to Radiator


Leave the cap OFF

CHECK FOR LEAKS..

If leak free.. start engine..

Let it idle until warm.. the level will rise in the radiator..

Bubbles will work their way free

When radiator fan runs.. the coolant level will drop


You can then turn off engine

Let cool

Add fluid to the MAX mark


That will have coolant circulating correctly

The system will still shift small pockets of air.. so keep an eye on the level for a few days of use

http://4cardata.info/elearn/312/2/312000000/312000000/312000003/312000484
That is for fiat 500 but it is very similar .

Sometimes it's easier to remove the lower hose from radiator than remove drain screw/plug as Charlie suggested.

You could well have a leaking pipe that sits under the exhaust manifold, it's very common, only held in by one bolt but a pain in the bum to replace. It's a fairly cheap part.
This guide shows how to replace it:
https://www.fiatforum.com/punto-mk2-2b-guides/193395-how-replace-steel-coolant-carrier-pipe.html

Head could be going, standing in front of car facing engine look under air filter on right
Side , you will see a small green sensor bolted to engine , unclip plug and fan
Will come on in seconds and stay running, the engine warning light will come on but will go out not long after re connecting plug

Fialfa said:

Head could be going, standing in front of car facing engine look under air filter on right
Side , you will see a small green sensor bolted to engine , unclip plug and fan
Will come on in seconds and stay running, the engine warning light will come on but will go out not long after re connecting plug

Click to expand...

I did and nothing happened and temperate gauge stoped working, i short the connection with help of paper pin, and started working, even when engine was switched off

Ok well when you have car running and you disconnect the temp sensor plug the fan should come on usually within seconds so I think this is your problem and the car cannot tell when car needs the fan , your sensor may be cooked in that case and you need to change it and try again if it fails to start fans with new one check the wiring but I think you just need a new temperature sensor they are cheap and just bolt off and on also check your coolant levels and that bottom hose gets hot when car is up to temp as this may have also cooked your thermostat / hopefully not