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Smaller eletric fans on the passenger side not working when hot??


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The fan in the shroud is for the AC I believe and comes on only under certain conditions, whereas the slightly larger fan on the other-side of the rad is controlled by a thermal switch at the bottom of the radiator and only comes in when the viscous fails or can not cope, rarely. There is a thread on here where CW explains it in this way. The autobox cooler is simply a single pass in the bottom tank of the radiator therefore can not have it's own fan, instead relying on the coolant, stat and viscous/electric fans to maintain the temps within a comfortable range.

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The fan in the shroud is for the AC I believe and comes on only under certain conditions, whereas the slightly larger fan on the other-side of the rad is controlled by a thermal switch at the bottom of the radiator and only comes in when the viscous fails or can not cope, rarely. There is a thread on here where CW explains it in this way. The autobox cooler is simply a single pass in the bottom tank of the radiator therefore can not have it's own fan, instead relying on the coolant, stat and viscous/electric fans to maintain the temps within a comfortable range.

 

dont agree totally you might have the fans around the wrong way,

As i know for a fact that my fan in the suround come on when i was accelerating hard and braking hard for a little time and when i pulled up the fan was on,so yes could well be a over flow type thing for the viscous fan, but not the a/c as i didnt have it on

best way to tell is look at the manuals on the front page and see if a stock tt6 has one or if its named in the manuals

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Coolant section of the WSM Page CO29 has all your answers

 

They are an electric back up for the viscous fan to assist engine coolant cooling

 

PS: if your going to check if their seized use a piece of wood or similar just incase

they come on ;)

 

Reminds of an incident with a mincer at work, we used to call the guy stumpy. It's amazing how stupid some people are :blink:

Edited by Tyson (see edit history)
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dont agree totally you might have the fans around the wrong way,

As i know for a fact that my fan in the suround come on when i was accelerating hard and braking hard for a little time and when i pulled up the fan was on,so yes could well be a over flow type thing for the viscous fan, but not the a/c as i didnt have it on

best way to tell is look at the manuals on the front page and see if a stock tt6 has one or if its named in the manuals

 

Are you sure that what you are hearing isnt the larger electric fan in front of the rad? On mine the smaller fan comes in only in really hot conditions when the AC is on.

 

The larger fan I have only had switch in after several foot on brake at 2000 rpm while in drive launches at pod. Also, the sensor plug at the bottom of the rad has normally closed contacts, so if you pull the plug on the sensor the relay operates and the large fan comes on regardless of the temp making it very easy to check. I tried this on mine last night and sure enough only the large fan kicks in, not the smaller one in the shroud suggesting this is triggered from another sensor or at least the relay to this gets its supply on when the AC is on at the same time as the larger fan has been activated.

 

CW and LeeP also seem to go along with this:

http://www.mkivsupra.net/vbb/showthread.php?69226-Electric-Fan-on-the-rad&highlight=small+electric+fan

http://www.mkivsupra.net/vbb/showthread.php?271364-Plug-at-the-bottom-of-the-rad&highlight=small+electric+fan

 

So maybe there are variations, but that would surprise me (other than between UK and Jspec). Would be nice to know for sure.

 

 

Coolant section of the WSM Page CO29 has all your answers

 

 

They are an electric back up for the viscous fan to assist engine coolant cooling

 

PS: if your going to check if their seized use a piece of wood or similar just incase

they come on ;)

 

Would you send me a link to this please Dunk. Is it possible that there were changes through the production run, or differences in models?

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It's a facelift - they have additional fans!

 

There is a connector near the bottom of the shroud/radiator - is it deffo attached? If you are out of options, cut the red wire (assuming you can solder and shrink wrap back together) and they run with just the ignition on...to prove they are working.

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It's a facelift - they have additional fans!

 

There is a connector near the bottom of the shroud/radiator - is it deffo attached? If you are out of options, cut the red wire (assuming you can solder and shrink wrap back together) and they run with just the ignition on...to prove they are working.

Indeed, that page shows two fans in the shroud not one. I can't see any reference to the larger electric fan in front of the radiator. So that info does not apply to all models.

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Will take a photo of mine later. Its a 95 TT jspec. The sensor at the bottom of the rad operates the larger electric fan in front of the rad on mine and not the smaller fan in the cowl. My cowl looks the same though with a single fan and not with two as in the link to the wsm.

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Page 242 of the wsm shows a NC water sensor (one in the bottom of the rad ) in series with a NC AC pressure switch in the relay control circuit. Bear in mind when you disconnect the water sensor the fan kicks in as its a NC sensor, then the same will happen when whatever pressure the AC pressure switch is monitoring tells it to open. So it seems on the application that that particular cct is for, the fans can be triggered either by water temp or a/c pressure.

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