Blower motor running constantly - even when car locked. Help!

GeeDog · May 15, 2021

Anyone had this before? 2013 Cayman S:

Fresh air blower motor running full speed constantly, even when car switched off and locked.

Control system apparently working in auto and manual (bars for fan speed increase/decrease), but fan stays at max speed regardless. System can even be set to read OFF and the fan's still at it. Left car for five minutes locked, still running.

I've pulled the 40A fuse for the blower to save the battery. Any thoughts?

Thanks in anticipation. I tried searching the forum but didn't find anything. Help!

Motorhead · May 15, 2021

Graeme,

It sounds as though your problem could be due to a faulty blower regulator:

https://www.pistonheads.com/gassing//topic.asp?h=0&t=1701521

If that doesn’t fix it then maybe the fault is with the HVAC module, in which case a PIWIS or equivalent diagnostic check should verify the cause.

Jeff

BrianJ · May 15, 2021

Seems quite common. For pictures of the fix see p2 of https://www.boxa.net/topic/71860-981-cabin-blower-wont-stop/page/2/

Good luck!

GeeDog · May 15, 2021

Great stuff, thank you. It does very much sound like that, yes. Will investigate and report back.

Edit:

For future reference: Design911 have the OEM (Hella) part for £43.65, so have ordered. Worth a punt. Part No. 99162442301/1

https://www.design911.co.uk/fu/prod132925/Air-Conditioning-Blower-Regulator-Porsche-991---981/?source=doofinder

Same part in a Porsche box is 99162442301 = £127.76. But I'm a Yorkshireman. It's against my religion.

Tune in next week for another exciting installment etc etc...

Graeme

Kaiser981 · May 15, 2021

I had the same fault as you describe and used the Hella part. Quick 15 minute job and sorted the problem instantly.

GeeDog · May 19, 2021

Update. Replacement 'hedgehog' regulator did the trick. Design 911's OEM part appears to be the same as the original (date stamped 13/3), for info. Trickiest bit was getting fingers in to depress the tabs and pull the plug. Easy enough.

Thanks for your help, all. Pics of offending part, for future reference. (With head in passenger footwell, look up, remove panel – plastic trim screws – and you can't miss it.)