‘’75 Fan Relay

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4Judy66
Posts: 2
Joined: Thu Jul 04, 2024 11:45 am
Your car is a: 1975 124 Spider

‘’75 Fan Relay

Post by 4Judy66 »

Hello,

Anyone know where to find a 3-pin fan relay for a ‘75 Spider? I checked the usual spots, Vick’s, Midwest Bayless, Autoricambi, eBay, etc and only find 5-pin relays.

Cheers!
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: ‘’75 Fan Relay

Post by 18Fiatsandcounting »

Are you sure it's not a 4-pin relay? The cooling fan relay should be the middle one in the row of three that is closest to the engine, on the driver's side firewall, although there were differences in model years.

Here's how it works: The cooling fan should be grounded through a black wire direct to ground. The fan relay receives +12V from a light blue/black wire ultimately to the "input" of Fuse 10. When the radiator switch reaches a set temperature (usually 200 degrees or so), it closes and sends a ground signal to the relay through a white/black wire to the relay (black wire at the relay). When the relay is grounded, it closes and supplies +12V through a violet wire to the fan motor, and the fan turns on. The violet wire is connected to Fuse 1, so the cooling fan is fused through Fuse 1.

Chris Obert at fiatplus.com has a 4-pin relay if that's what you're looking for. But also check fuses 1 and 10, and make sure your thermostatic switch at the bottom of the radiator is working.

-Bryan
4Judy66
Posts: 2
Joined: Thu Jul 04, 2024 11:45 am
Your car is a: 1975 124 Spider

Re: ‘’75 Fan Relay

Post by 4Judy66 »

Thanks for the reply. The relay I pulled and tested was three point. Could be I have the wrong relay to begin with.
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: ‘’75 Fan Relay

Post by 18Fiatsandcounting »

4Judy66 wrote: Sun Sep 15, 2024 12:13 amCould be I have the wrong relay to begin with.
Could be. All the wiring diagrams that I have show a 4-pin relay.

-Bryan
spider2081
Patron 2024
Patron 2024
Posts: 3015
Joined: Fri Jan 27, 2006 11:45 pm
Your car is a: 1981 Spider 2000
Location: Wallingford,CT

Re: ‘’75 Fan Relay

Post by spider2081 »

I don't know of any 3 pin relays. 2 pins are used for the relays coil and either 2 or 3 pins are used for the relays contacts For the Bosch style relays used by Fiat pins 85 and 86 are the relays coil. Pins 30 and 87 are the normally open contacts and pins 30 and 87a are the normally closed contacts. Some of the relays have 2 pin 87. There is a Timer device that resembles a relay,in appearance, that has 4 pins labeled +, -, C, and C1 This is not a relay but a timer device used to light some warning lights for about 10 seconds. I don't know of any 3 pin devices other than the turn signal flasher and that is round while relays are usually square.
85redpini
Patron 2018
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Posts: 86
Joined: Sat Nov 03, 2012 12:51 pm
Your car is a: 1985 pininfarina spider

Re: ‘’75 Fan Relay

Post by 85redpini »

4Judy66 wrote: Fri Sep 13, 2024 4:50 pm Hello,

Anyone know where to find a 3-pin fan relay for a ‘75 Spider? I checked the usual spots, Vick’s, Midwest Bayless, Autoricambi, eBay, etc and only find 5-pin relays.

Cheers!
we have the oem fiat one in stock, but you passed on it
spider2081
Patron 2024
Patron 2024
Posts: 3015
Joined: Fri Jan 27, 2006 11:45 pm
Your car is a: 1981 Spider 2000
Location: Wallingford,CT

Re: ‘’75 Fan Relay

Post by spider2081 »

we have the oem fiat one in stock, but you passed on it
Are you saying you stock a 3 pin relay used for the coolant fan???
Although I don't trust the accuracy of the wire diagram I have for a 1975 Spider, It shows a 4 pin relay controlling the engine coolant fan.

4judy66's post is looking for a 3 terminal coolant fan relay.
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