side fans

[taylor.v6]

Just after some advice on the side fans. The vee has had a couple of occasions where it's started to overheat and I noticed the side pod fans don't work. I done a quick search on here and saw you can swap the fuse with the AC but still no joy.

Is there anything else I can try, or if anyone else's stopped working what was the outcome if you got them repaired. Hopefully not too expensive

Cheers

 

[Brett]

If its over heating have you checked the front fans? The rears don't actually do a great deal as they push no cool air through the rads what so ever.

 

[taylor.v6]

Yeah front seems to be working fine, it's more when it's in traffic when been standing for a while

 

[Spike]

try looking at the temp sender mounted on the rear bulkhead, little thing with 2 wires

 

[taylor.v6]

I think I know what you mean, but I'm useless with cars. What would I be looking for and what would that do if it's not working properly

 

[Jamesv6]

Picture of it here LINK

 

[Kevred]

IS your overheating just the temp gauge creaping up past the normal half way position ? or is it actually overheating to the point where you have to turn it off because its loosing water ? I suspect the first one , :s

 

[taylor.v6]

Doesn't seem to be loosing water, it creeps up when stationary for a while. On the move it goes back down to nornal

 

[martinr82]

@taylor.v6

Not sure if I have a similar issue on mine or not, as I dont know what the resistance of the temp sensor is meant to be. I have a feeling its a temp switch, as when its cold its open loop, but hoping someone can shed some light on it.

 

[Hillman]

Reading this thread has now got me wondering about my car. My coolant temp is fine, even in hot weather, but I've never heard the pod fans come on. I presume their purpose is to clear the heat build up in the engine compartment after you stop, so their operation is not linked to the coolant temp at all? I've got power to the sensor so it's not a fuse if there is a problem with mine.

 

[Jamesv6]

Put a hair dryer near the sensor, maybe that would test it?

 

[Hillman]

Thanks for the hint! I tried it and no luck, though I don't know how hot it needs to be. Anyway, I've found the fans still don't work even when I directly connect the sensor wires, so maybe the relay is the problem ... Does anyone know which one it is?

 

[Jamesv6]

LINK

 

[Hillman]

Thanks again James.

 

[cjm307]

This may be old news but thought I would post some info on the front and side cooling fan wiring,

Front cooling fans
The front fan units are controlled by the injection computer using the coolant temperature signal from the injection system.
2 terminals on the injection computer switch to earth at specific temperatures. (99˚C and 102˚C).
Depending on which terminal is earthed, relays connected to the terminals (located in the inner front wing) are activated.
The circuitry between these relays (x3) allow a series or parallel wiring arrangement to the fans (high and low speeds) depending on which terminal is earthed.
If the front fans are active and the temperature in the engine compartment is greater than 70˚C ±10 whist the engine is running, the rear fans are actuated.
Please note: Rear fans can only be actuated if the front fan units are active.

Anti-Percolation after engine switch off.
If the coolant temperature exceeds the limit of 102˚C during the 10 minutes after the engine is switched off, the front fan unit is controlled at slow speed. If the coolant temperature falls below 95°C, the front fan unit relay is cut off. Likewise, if the temperature in the engine compartment is greater than 70˚C ±10 after stopping the engine, the rear fans are actuated. Rear fans will only be actuated if the front fan unit is active.

 

[Kett]

Great info and a bloody good read, Chris.
: )

Moderators:
This needs to be uploaded to 'The Knowledge'.


Sent from my iPhone using Tapatalk

 

[PeteH]

Just for info, I recently changed that temp sensor on the rear bulkhead.

The old one had cracked due to age. When broken the side pod fans where coming on all the time, even before it hit normal running temp..

all good now tho with new sensor, about £25 quid..

 

[hualpa_jo]

the side pod fans where coming on all the time, even before it hit normal running temp..

You mean whenever the radiator fans are running? Because they can't run on their own.

I bridged this switch to get just that behaviour. Because I almost never use aircon they run whenever the radiator fans are running and that's only when the engine is on temperature. I noticed that during "Anti-Percolation" only the front fans ran although some fresh air wouldn't hurt the engine and for me this configuration has no downsides.

 

[cjm307]

Pete, interesting info

I tried bridging the side fans switch on mine to see if they could be activated, nothing happened until the low speed front fans kicked in.

This then led to my investigation above,

After the new switch was fitted on yours , do the side fans still activate regardless of the front fans?,

On another note , the switches are ksd301 type . ( Search ebay ksd301 ) there is various terminal arrangements, temperature ratings , interesting ( as you will know, the type Renault installed have a stud which seems to be a rarer arrangement of this switch).

 

[PeteH]

Since fitting new, side fans have only activated the once on a very hot day in traffic and so seem to be working as they should..

And had actually expected them to do so after the previous open road