Heating Problem After Replacing Coolant

[omri617 18]

make sure nothing has been disturbed when draining/replacing the coolant, level is fine and heaters get hot ( normaly somewhere near bled through if they get hot) as stated put 12 volts to the fan best way be with a power probe or lenth on wire

If all of the above is ok (witch cost nothing) then start checking things like the temp switch , relays and resistor etc. and on a rare ocasion the wiring harness , normal diagnosis methods to rule out the problem , you should be able to sort it wiith a multi meter and wiring diagram

 

What have you checked so far?

 

Switch on radiator wires connected - even changed the polarity.

Took them out to see if there are any cuts.

Bridged them - heard relay clicks - but no fan.

Fan gets into action when pressing the AC button so it's not fried.

[DamirGTI 344]

You can spot an air lock inside the cooling system by , turning the heater on (engine on working temp.) and by placing your hands on the vents and if you sense that it blows hot then cool air repeatedly mixing temp. of the heating intensity .

 

If it's an air lock within the system , so it can "disturb" the thermoswitch sensing the temperature as well i suppose , more that that it can do major damage to the engine creating steam pockets around the block/cylinders head coolant passages and thus thermal stress which leads to metal cracking ..

 

D

[Zacky-94 7 2 Cars]

Personaly by the sounds it would be to do with the swtch or relays but first thing i would be doing is checking its bled properly and there is enough fluid etc in it the thermostat is opening (run it up till its hot and make sure the top and bottom hoses are hot if bottoms cold then it isnt working properly And circulating

, if u dont think its working then take it out boil the kettle and drop it in the boiling water u should see it 'open'' (simplest method), i cant see it being anything serious as it worked before ,

it will be ok on open roads because it is getting cool air to it as u pick up speed etc. And in traffic there is no cool air going to the rad or engine its stationary so it heats up alot quicker,

[Zacky-94 7 2 Cars]

Are there seprate relays for the AC and coolant switch? I dont know enough about the xu's to say to be fair , i work on bmw's lol

[DamirGTI 344]

Dunno about AC cooling fan system on 205 .. never seen one .. all non AC 205 cooling fans are separate loom and do not have relays .

 

D

Edited March 19, 2013 by DamirGTI

[omri617 18]

I believe in my car , the ac wiring to the fan is direct without relay. it operates constantly when pressing the AC button , never mind the operation of the compressor / temp. status

[Zacky-94 7 2 Cars]

Just seems strange that it works through the ac but not when the engine is hot , just try all the bit people have mentioned and see where it gets you

[omri617 18]

UPDATE :

 

Checked the fuses in this compartment (by mistake and there was it . 30 AMP fuse blown.

thanks all

[DamirGTI 344]

Keep an eye on it for a few days , cos there must be some reason why it blown out .. and it's a 30A fuse so lots of current there .

 

Could be just by mistake shorting some of the circuit wire .. but it might problem within the wiring as well .

 

D

[omri617 18]

If it does blow the fuse again , it can indicate for what?

thanks Damir

[DamirGTI 344]

Wiring problem (positive touching ground) , sized fan motor etc ...

 

D