Electrical question
Thread Starter
OkRider
Rennlist Member
Rennlist Member
Joined: Jun 2010
Posts: 5,582
Likes: 169
From: Oklahoma
Electrical question
Hi guys, I was going to drive the 968 yesterday, but the battery was totally dead. Figured I left something on so I put it on the charger and took the bike instead. This morning all is good so I drove it to work. Made one stop on the way and noticed that the fan/fans were running after the engine was shut off. Unusual in this cool weather and light traffic. Whatever, did my business and back in ten minutes and the fans were off. Drove two miles to work and the fans are on again. I go in and come back out a couple minutes later...still on. Now I'm really curious. Pop the hood and see that both radiator fan motors are running. I pull the fan relay and they stop, of course. Went out an hour later plugged the relay back in and both fans come back on.
Any ideas? My first thought is a bad relay, it sounds a little rattly on the inside. It was a little warm to the touch when I removed it the first time too.
Thanks
Any ideas? My first thought is a bad relay, it sounds a little rattly on the inside. It was a little warm to the touch when I removed it the first time too.
Thanks
Rennlist Member
Joined: Jul 2013
Posts: 3,052
Likes: 452
From: Wilbur by the Sea, FL
I would say the fan switch....easy enough to test. Obviously the relay works, and you almost never hear of a "stuck" relay, only one that fails due to the contacts going bad or the coil open circuiting. Normal failure mode of a relay is deenergized
Racer
Joined: Jun 2011
Posts: 290
Likes: 0
From: Portland, Or.
Paul's logic sounds good. I'd also start with the fan switch, unless you have a relay to swap since that would be easy to rule out. Is there another relay in the fuse area that is identical?? Don't know enough about that area to know.
Thread Starter
OkRider
Rennlist Member
Rennlist Member
Joined: Jun 2010
Posts: 5,582
Likes: 169
From: Oklahoma
Thanks guys! I'll check out the fan switch, not sure where its located though. Probably run up the road and get one in a bit. 
I will report back when I'm convinced its fixed.
I will report back when I'm convinced its fixed.
Rennlist Member
Joined: Jul 2013
Posts: 3,052
Likes: 452
From: Wilbur by the Sea, FL
I don't know where the sensor is either....but it would make sense it's on the engine vs. the radiator....my guess is near the intake manifold.
It has three wires, all 1.5 mm (regular looking wires, not HUGE, not TINY), one is red/white stripe, one is brown and another is brown/yellow stripe.
The brown is the ground, it goes to ground connection 36.
It has three wires, all 1.5 mm (regular looking wires, not HUGE, not TINY), one is red/white stripe, one is brown and another is brown/yellow stripe.
The brown is the ground, it goes to ground connection 36.
Trending Topics
Thread Starter
OkRider
Rennlist Member
Rennlist Member
Joined: Jun 2010
Posts: 5,582
Likes: 169
From: Oklahoma
Rennlist Stories
The Best Porsche Posts for Porsche Enthusiasts
Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture
Verdad Gallardo
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look
Verdad Gallardo
10 Porsche Colors That Have More Personality Than Most People
Verdad Gallardo
Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod
Verdad Gallardo
10 Reasons I Hate Going to the Porsche Dealership (& the 1 Reason I Stay)
Joe Kucinski
Porsche Shakes Up The Nürburgring Lap Record Table Once Again
Verdad Gallardo
6 Ways the Porsche 911 GT3 S/C Redefines Performance
Joe Kucinski
10 Wildest Homologation Specials Porsche Ever Sold
Verdad Gallardo
Super Rare RUF BTR III Comes Out of Hibernation, Looking For a New Home
Verdad Gallardo
Thread Starter
OkRider
Rennlist Member
Rennlist Member
Joined: Jun 2010
Posts: 5,582
Likes: 169
From: Oklahoma
I don't know where the sensor is either....but it would make sense it's on the engine vs. the radiator....my guess is near the intake manifold.
It has three wires, all 1.5 mm (regular looking wires, not HUGE, not TINY), one is red/white stripe, one is brown and another is brown/yellow stripe.
The brown is the ground, it goes to ground connection 36.
It has three wires, all 1.5 mm (regular looking wires, not HUGE, not TINY), one is red/white stripe, one is brown and another is brown/yellow stripe.
The brown is the ground, it goes to ground connection 36.
Thread Starter
OkRider
Rennlist Member
Rennlist Member
Joined: Jun 2010
Posts: 5,582
Likes: 169
From: Oklahoma
Ok, it appears that the switch is on the radiator drivers side, upper corner under a coolant hose. OK Foreign out of new stock. Was told it was a pretty available through the regular parts stores. Also switch is in common with a VW one too, I'm told.
BTW, when I pluged the relay in after sitting for 6 hours the fans came on. Relay didn't smell burned either.
Off to NAPA.
BTW, when I pluged the relay in after sitting for 6 hours the fans came on. Relay didn't smell burned either.
Off to NAPA.
Rennlist Member
Joined: Jul 2013
Posts: 3,052
Likes: 452
From: Wilbur by the Sea, FL
If you have a multi meter, put it on resistance, and measure the resistance between 1 and 3 and 2 and 3. This would tell you if the 92 C switch is closed (2 and 3) or 102 C switch (1 and 3) is closed....that way you can verify it failed.
Less than 1 ohm, it's closed, greater than 1,000 ohms (should read MUCH higher than that) it's open.
Less than 1 ohm, it's closed, greater than 1,000 ohms (should read MUCH higher than that) it's open.
Rennlist Member
Joined: Jul 2013
Posts: 3,052
Likes: 452
From: Wilbur by the Sea, FL
And I see Clark's Garage already has almost all of this:
http://www.clarks-garage.com/shop-manual/cool-01.htm
http://www.clarks-garage.com/shop-manual/cool-01.htm
Thread Starter
OkRider
Rennlist Member
Rennlist Member
Joined: Jun 2010
Posts: 5,582
Likes: 169
From: Oklahoma
Thanks very much Paul and Tamathumper, it sure is pointing to the switch. Ordered a new switch from the local NAPA, be in tomorrow. I have a Fluke 23 series II multimeter to check the old and new switches. I am very unhandy around electrical stuff unlike most of you guys. I appreciate the guidance and the Clark's Garage link. 
Thread Starter
OkRider
Rennlist Member
Rennlist Member
Joined: Jun 2010
Posts: 5,582
Likes: 169
From: Oklahoma