Engine compartment fan failure warning - but fan running

[Windy_Miller]

?Hi All,

This is on my 987.2 CS, but I suspect it’s a similar system / set up on all caymans, and boxsters.

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 ??????????????????
?
thanks, Jason

 

[DWaldie]

Thanks for the info. Keep us updated. Have you tried the autodoc website. They are German based site and often have OEM parts.

 

[Motorhead]

Hi Jason,

Unfortunately I can't speak from experience, but in the absence of a Porsche-specific diagnostic check I'm inclined to agree with your logic. I think that replacing the temperature sensor is a good first move, but if that doesn't work I guess that a trip to a Porsche Centre or Porsche Independent for full diagnostic check is the only way forward if you don't want to get into swapping-out components haphazardly.

Incidentally, I've just received notification from a couple of Porsche Centres that they're closed for face-to-face business, with the service departments only available for key workers and carers and to provide customers with essential aftersales support, but you may be able to get the parts department of your Centre to post the sensor to you.

Good luck!

Jeff

 

[Windy_Miller]

Thanks Gents,

Just looked on autodoc and the particular sensor (99760621300) doesn’t seem to be stocked by them. Design 911 have it, but like most things they charge the OPC VAT inc price, and then add VAT, and charge P&P, so an OPC £22 sensor would cost £36 from D911.

I hadn’t thought of ‘mail

order’ from an OPC - that’s a good idea, which I’ll try tomorrow from silverstone

It’s not essential right now as not intending to drive much currently, but will report back on the eventual fix.

 

[Windy_Miller]

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