Porsche Enthusiasts Club Forum

had the car off the road for a couple of months and on recent start up electrics played up ( see recent post ) but now things seem to have settled down.
Only problem now is the cooling fan which starts running as soon as the battery is connected. Running the engine doesn't make any difference ,only stops when battery is disconnected.
I am guessing it must be a faulty sensor but could the relay be part of the problem?
As usual thanks for your help.

It will be the switch in the top of the rad under the top hose

The fans came on and were a bit stiff after being laid up for a while, the extra load welded the connections together inside the switch

Need a 32mm socket to remove and replace the switch

I picked up my 1984 Guards Red 2.5 lux just before Xmas, so I'm a new forum member and this my 1st post. I drove the car back from West Sussex the day I bought it, ran faultlessly. Got home and it was getting dark, I managed to get the Wife to come outside to look at it about an hour later, as I was proudly showing her my new daily driver she said whats that noise? Now the car had been standing, engine off since I got home, it was the rad cooling fan! So I disconnected the earth lead, went out the next morning and reconnected it and the fan did not come back on, I thought Happy days all ok ...Wrong! The following morning went to start it up to go and drop my wife up to collect her car from the pub, battery flat as a Witch's Tit. So I charged it for 24hrs and it started no probs, I called Peter who I had the car off (Porsche Technician) he was surprised as the car had been in his garage for a couple of months until a few days before I collected it, and when he took the car into work to service and mot it for me it fired up no probs at all. When I explained about the fan running when the engine was off he advised that it was probably a faulty fan switch which is located just under the top hose on the radiator, he very kindly emailed the Euro car parts Valeo Radiator Fan Switch Part no: 223330030 the RRP is about £28 I work in the Motorcycle trade so it ended up costing £14 trade. It took about 10mins to fit the switch (you can get to it from the l/h side its located on the right) after running it up to temp to make sure the fan was cutting in there didn't appear to be any loss of coolant, but checked a few days later and it had dropped to just below min. The fan now doesn't run when engine is turned off and its been all good since.
I hope that this helps you.

Nick

just replaced the fan switch and the fan still runs all the time.
Any ideas where I should look next ?
Thanks

There is a full test sequence for the rad fans on Clark’s Garage

The only things that control the rad fan are the switch in the rad and the relay in the fuse box

http://www.clarks-garage.com

You need section cool-01

Mine was caused by the relay, the connectors where corroded.