Radiator fan is always on when engine is running + 2 min after

[vlad1981]

Hi guys. My other issue is radiator fan. It is always on as soon as you start the car + about 1,5 min after you turn the "ignition off". I had it disconnected during winter but now trying to fix it. I have checked (and tried 1 of another vehicle) the sensor in the radiator hosepipe (that leads from the engine to top of the radiator) - still no luck. Any ideas? Thanks

 

[holtie]

Did you ever solve rhis problem as mine does this. Thanks

 

[vlad1981]

In my case it was faulty coolant temperature sensor. There are two sensors sitting on the same pipe that goes from top left corner of the radiator to top right side of engine block (as you look at it with the bonnet open). One was stuck at HOT which resulted in fan being constantly on + air con wouldn't work. Ecu wouldn't allow it to work thinking car was overheating and working aircon would put extra strain on the engine. Go to scrap yard and try them of other car see if it helps. When you take them out a little bit of your coolant will come out with them so don't do on hot engine.
You may find that after fixing fan issue car will take few more seconds to start but that is another story. Good luck

 

[holtie]

Thanks for the reply. I will take a look later but I cannot recall seeing any sensors there. Is yours a 130bhp engine with code ASZ as they seem to be different from other models.

 

[vlad1981]

Just looked at picture of ASZ engine. No, I had a different one. check pipes to and from radiator or exploded diagram of your engine and try to find sensors. I'd start with them

 

[holtie]

Will do. I had a check a few weeks ago but couldn't see any (only one in the pipe going into the radiator but I've been told that's for the gauge which is reading correct). I didn't pay too much attention to the ones from the rad though.

 

[vlad1981]

That gauge one could still be faulty. It can be a dual one feeding info to the gauge and ECU (most likely then will have 4 wires goung into it). Easiest way is to check exploded diagram of ASZ cooling system

 

[holtie]

got a new temp sender that fits in the pipe at the bottom of the radiator and that seems to have sorted it. I think the temp gauge reads from a different one on the right hand side of the engine in an impossible to get to place! Thanks for your help

 

[vlad1981]

If you are interested to know if the one you changed controls the gauge as well and its easy to get to you can unplug the wires when the car is warm and see if you have any temp reading on the dash.

 

[holtie]

I did that yesterday and the gauge was still reading. I tested the resistance of the one I took out and found it to be around zero. I cant remember the resistance of the new one but I know it dropped as it got warmer. Now I need to sort out why my alternator is only giving out 12 volts sometimes on startup until I get upto 1500 rpm - think it may be something to do with the small wires plugged into the alternator (I've put extra earth wires on alternator to engine and engine to bodywork as well as replacing the main alternator cable to the fused link which was a bit melted)

 

[vlad1981]

Just a thought: Is the belt vibrating at all? There is a clutch mechanism inside alternator pulley. If its faulty that may result in insufficient alternator voltage on low revs

 

[holtie]

I checked the pulley mechanism yesterday and it was fine. The belt does vibrate a little. After the voltmeter reads around 14 volts it never drops down again until next startup and then not all the time. At the moment it is acting normal but if it keeps doing it I will try a new voltage regulator

 

[holtie]

2 days running and the voltmeter is going up to 14 volts so it looks like there was a bad connection on the small wires at the alternator. Still keeping my fingers crossed though.