A new fan problem

[PranK]

Hi All,

Last week I was driving home and, considering it is winter, I didn't have the climatronic on at all. I was in some pretty heavy traffic and happened to look down to see my temp gauge was quite high - getting close to the very right hand side of the gauge. This is a temp i've never witnessed in my car (when my car had the cooling probs a few years ago the temp sensor was dead which meant my gauge never moved past 90, even when it was cooking itself).

When I flicked the A/C on, the fans immediately came on high speed and brought temp right back to 90 before turning off (Couldn't hear if they were on low speed or totally off). I drove the rest of the trip with a/c on and the car was fine.

When I got home I replicated the same situation, a/c off, sitting in the driveway with no airflow and kept revs at ~1500. Sure enough the temp started to climb again and I was just waiting for the fans but nothing happened. As soon as a/c went on again, fans blasted the engine and temp returned to 90.

So, I've proven that the engine is hot enough for the fans, so its not a matter of temp.

The fact is, the fans wont turn on when a/c is off.

My q - could this be the fan controller? I wouldn't think so as fans behave normally with a/c on. So, maybe the fans switch on the radiator? I did replace the switch last year but, maybe I need to check the switch again?

THanks guys.

[Bora Sport]

My recollection is that whether the engine is hot or stone cold the low speed fan will come on if the air conditioning is on. If it doesn't then it sounds possibly like the old low speed fan resistor problem. If you search this forum there is plenty of advice and recommendations for how to fix it. What used to happen was the low speed fan would stop working because the wire inside the fan motor breaks. Then when the engine gets hot enough, the high speed fan should come on but that would send a power surge through the fan control module and eventually blow it.
A guy in the U K I think it was, came up with an external resistor board which allowed you to continue to use the existing (broken) fan ie not have to purchase new fans. I did the modification on my Bora when my fans stopped working when it was about 4 years old. The car now is 16 years old and has 350,000k's on it and it still has both of the original fans in it.

[PranK]

Thanks Bora Sport, I've actually done the resistor mod already.

I focused a lot of effort on these fans when I did a bit of work to my cooling system a while back. They *were* running properly a few months ago. The only thing I haven't actually changed is the fan module which is why I'm wondering whether I give that a try next.

I'm stoked to see that yours has done 350ks! Is that the original engine? My goal is 300ks, I have 60 to go.