Engine compartment fan failure warning

[Windymiller]

Posted here as suspect it’s relevant to all models of Cayman, but this is on my 987.2 CS. 
 

since Friday last week I’ve had a dash warning repeatedly come up (in the main info area in the Rev gauge) stating, ‘engine compartment fan failure’, and then the red light at the far right of the engine water temp gauge flashes at ~1hz.
 

this light (flashing at different rates, or on solid) indicates different faults. The ~1hz flash is that the engine compartment is too warm (ie that the fan is not venting out the warm air). 
 

This is the fan situated behind the right hand side (UK driver side) rear quarter grille. It’s purpose is to draw warm air out of the engine compartment. It operates at 2 speeds and generally comes on if/when the car is stationary in traffic, or once parked up and switched off after a longer drive. It then runs for a few minutes to vent out the warm air from the engine bay. 
 

despite the warning light telling me the fan had failed it clearly hasn’t as I can hear it operating seemingly constantly after the engine warms up, and runs after parking up and getting out. 
 

I’ve researched the usual forums (planet 9, pistonheads etc) and a typical issue is that the engine compartment temperature sensor has dislodged from its Position between the intake plenums on the engine and has dropped down on its short loom to rest on a warm part of the engine. 
 

I’ve accessed it by removing the top engine access cover and it was in correct position and no apparent damage. 
 

sometimes, after a while, the warning and dash light just clears itself. 
 

ive not checked relays / fuses but I’m presuming that these are fine as the fan is working. 
 

so my ‘diagnosis’ is the temp sensor must be faulty, and is always reading the engine compartment is over hot, ergo the control unit ‘determines’ the fan must have failed as it’s not cooling the compartment down, and is also constantly telling the fan to operate. 
 

thoughts / similar experiences anyone? 🤔

 

im planning to change the sensor - its only £22 from OPC, but no chance of getting one this side of zombie-plague nation COVID lockdown 🧟🧟‍♀️🧟‍♂️😱😯😷

Edited March 25, 2020 by Windymiller

[Windymiller]

Well I did ~400 miles and 6hrs of driving from Ayrshire to bucks yesterday and not once did the engine compartment fan warning light come on 🤔

 

and the fan wasn’t constantly / repeatedly operating as it had been previously. 
 

so now I’m wondering if it was just gremlins? 🤷‍♂️
 

I’ll wait and see if it happens again

Edited March 29, 2020 by Windymiller

[sevenfourate]

Good its ok at the moment. And that it’s not dislodged itself. Or perhaps would be ‘better’ if it had 🙄

 

£22 sensor sounds most likely 

(And not bank-busting if it’s not). But worth taking off / checking / cleaning connections, Earths etc in the interim ?

[Beanoir™]

I would agree with your thinking Jason, and would certainly try the temp sensor as the next step given it's a low cost item.  

 

Have you checked the coolant level and all of the obvious other cooling things?  Assuming the front rads are ok? 

 

[Windymiller]

1 minute ago, Beanoir said:

I would agree with your thinking Jason, and would certainly try the temp sensor as the next step given it's a low cost item.  

 

Have you checked the coolant level and all of the obvious other cooling things?  Assuming the front rads are ok? 

 

Aye Nick, I’ve kept an aye on the coolant level over the past week as it was totally drained and refilled for the front cross-over pipes and hoses replacement. I’ve topped it up with 1ltr of coolant and ~200ml of ionised water, having done about 1100 miles in the past week since collecting from Porschacare. 
 

Matt there said it might need some topping up as airlocks get released in the system through use. The actual engine (water) temp hasn’t moved beyond just above 80degC throughout the whole episode. 
 

I’ll get the sensor ordered post COVID and see what happens with any warning message reoccurrence 🤔