1st timer here, sure I'll enjoy my time and learn a lot. Problem is with a '95 Subaru wagon. Gets pretty hot, no fans come on with or w/o AC on. Was going to change fans Temp switch but can't find it. Hayes just shows arrow pointing under intake manifold. This hard to change? Larry

Have you checked the fuse(s) and relay(s) to make sure they're okay?

 

 

I think the fans are controlled by the ECM on your car, but I might be mistaken.

Have a look in the radiator. Same side as the top hose.

Here's a pic of the coolant temp sensor. It's under the passenger side intake manifold

http://www.main.experiencetherave.com:8080/subaru/images/injectors/DCP_2477.JPG

 

However, if the fans aren't coming on with the AC, then I doubt it's the sensor. I'd check the electrical connection to the fans, and the fan relays.

Josh,

 

Am I seeing a pair of temp sensors in that photo (the green being the overheat idiot-lamp switch)?

I converted my non-Subie with mechanical fan to an electric fan this summer.

Learned a lot about temp switches and relays.

 

Best part of my final installation is a relay that runs the radiator fan on low speed whenever I step on the brake. Got the idea from a bulletin board poster who did that for another car that kept getting too hot. In my installation, this relay is the primary device running the fan. It covers stop + go traffic of all types. Only occasionally does the temp switch kick in due to extended idling, hill climbing on a hot day or some such situation.

 

I definitely would do my level best to set right whatever went wrong on your car. But if it resists your best efforts, or if you need a solution in place while you search for the cause of the problem, a brake switch relay might be just the thing.

 

Just in case you want to do this and have no clue about relays:

It's an electrically-controlled switch. Basic type has 4 wires: 2 to control what the relay does (+ and -), they go to a coil inside the relay, and 2 more wires to handle the connection to whatever you're turning on and off (your radiator fan).

 

Splice a wire to the non-powered side of the brake switch. The side that's away from the battery, closer to ground. This gets voltage only when the switch is "on". This goes to one side of the relay's coil. The other side of relay's coil goes to ground. The other 2 terminals on the relay act as a switch. You can use them to power the fan's low speed circuit (make sure the relay is up to the amount of current the fan will draw) OR if the fan's own relay circuit is working OK, you can use it to work that relay. Usually a fan relay has a thin "hot" + wire that allows the fan to be powered when that hot wire is grounded. If that's the setup, you can ground that "sensor" wire via the 2 switched contacts on your added brake switch relay.

Did you test the fan(s)?

 

First, make sure it's OK mechanically. With the battery disconnected, give the fan blade a spin with your finger. It should spin pretty freely. I've seen some frozen fans in my junkyard searches, and some that only turn with lots of resistance. So this does happen, and of course that situation needs a fan replacement.

 

If it spins freely, apply battery voltage directly to the + lead for the fan - make sure it runs. Make sure the fan's ground wire has a good ground.

Could these fans have a ground location in common? maybe its corroded.

 

I dunno

Josh,

 

Am I seeing a pair of temp sensors in that photo (the green being the overheat idiot-lamp switch)?

 

Yeah, there's two. The first gen legacies had two temp sensors, the smaller (green) one goes to the dash gauge. The brown one goes to the ECU.

This may or may not be of some use

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/coolingfanwiringdiag.jpg

Thanks for all the input, I'll be checking these out this weekend. I got a Hayes manual so maybe I'll find all the fuses & relays to test:) The car is missing and running poorly now so will likely throw in some plugs and new wires. It has 100k and I've had it for the last 10k. Already had to replace the timing belt and all the associted gears pullys and bearings. Larry

 

1st timer here, sure I'll enjoy my time and learn a lot. Problem is with a '95 Subaru wagon. Gets pretty hot, no fans come on with or w/o AC on. Was going to change fans Temp switch but can't find it. Hayes just shows arrow pointing under intake manifold. This hard to change? Larry