Radiator Fans - again

[insite]

each fan has its own thermostat; they operate independently from one another unless the AC is on.

[madmods]

Originally Posted by insite

each fan has its own thermostat; they operate independently from one another unless the AC is on.

Just interesting learning. Seriously, what kind of engineering is this mate?! Another added possible point-of-failure or just cooling based on the Left & Right wind direction? fak sake....

shlim8's mechanic should have designed the cooling system, it would have been simpler and perhaps better imo

[shlim8]

Originally Posted by insite

each fan has its own thermostat; they operate independently from one another unless the AC is on.

Thanks insite for the reply.

Any ideas on what the part no is for the thermostat and where the thermostat is ? I re-looked at the pet catalog diagram and can't find a thermostat anywhere around the radiator. The thermostat should be measuring the temp of the coolant in the radiator (like normal cars) ??

If I have a radiator fan that seems to be on more often than the other side, does it mean that radiator is less efficient in cooling or hence fan is on, or the thermostat on the other side is not working well ??? Or water flow is less on one water pipe.... hmmm

In fact I've never had the left side fan come on without the right side fan being on (but the reverse happens).

Nothing is simple on a P car isn't it ??

[insite]

I think it actually measures the surface temp of the the radiator itself. The part number is 996.616.101.00. I actually have my radiators out right now; I'll take a pic tomorrow.

[Dale_K]

The fans in my 2000 S seem to work together. I've never noticed only one fan operating. The Durametric can bring them on in high or low but not independently. I could see if the big resistor failed on one fan you'd get a situation where both fans would run in high, when the resistor isn't used, and only one fan would run in low.

I'm not saying you're wrong, only giving my experience.

[shlim8]

Originally Posted by insite

I think it actually measures the surface temp of the the radiator itself. The part number is 996.616.101.00. I actually have my radiators out right now; I'll take a pic tomorrow.

That's actually the series resistor... I'm going to order those online and replace it just to be sure...

[insite]

They do call it a resistor, but it looks like a thermistor to me. I bet yours has failed.

[shlim8]

My fans have finally gone crazy....

Yesterday when I started the car from cold, the fan comes on - as the a/c was on, I thought it was normal... checked the front and only 1 fan (right side) was running at low. I turned off the a/c and the fan now goes in to high speed AND again it was only on the right side...

Drive for the next hour or so, stopping where ever possible to check the front fans - still only 1 fan running at either low or high... (so at this point in time I'm thinking great, it's much easier to fix a permanent problem that an intermittent one)

When I got home, both fans are on at high speed... I let it run till it cuts out. Then I turned the aircon on, both came on at low speed.... $#@!!

Summary:
Engine cold - a/c on = one fan on low, sometimes 2, a/c off = one fan on high, sometimes none
Engine hot - a/c on = sometimes one fan, sometimes two fan
Engine very hot - sometimes one fan on high, sometimes two fans on high...

Any ideas ? I'm still thinking that something must trigger the fans, the dme ? But the dme must get it's temp input from somewhere. Or could the relays cause this ?

The series resistor might explain one of the fans not coming on at low speed, but now the other fan is intermittently coming on even on cold starts ?? (at least fans coming on excessively is better than not coming on at all !!!)

[shlim8]

Where are the relays for the aux fans ? Are they in the back trunk ? And which one ?