Where is the fan sensor located at?

[562daybid]

Hey guys sorry I'm new to this forum and Toyota but I was wondering which one is the fan sensor? I think I might need to replace it. Btw I have a 97 Toyota Corolla CE edition with the 1.8 Liter 7A-FE Engine

Is it this one


Or This one?

[NWMO 95 Prizm Lsi]

562,

You are pointing at the fan sensor in the first photo.

Chris

[562daybid]

Originally Posted by NWMO 95 Prizm Lsi

562,

You are pointing at the fan sensor in the first photo.

Chris

Thanks alot buddy! I kind of figured it was that one since it was on the thermostat but I started to scratch my head when I saw only 1 wire. Usually there are 2

[562daybid]

btw what is the sensor on the second picture?

[562daybid]

Man this thread is dead. even with pictures I only get 1 response -_-

[Kiwi-Corolla]

Patience is a virtue . The one nearest the distributor is the thermoswitch and the other one is the coolant temperature sensor.

[562daybid]

Originally Posted by Kiwi-Corolla

Patience is a virtue . The one nearest the distributor is the thermoswitch and the other one is the coolant temperature sensor.

Yeah I should have waited but I got inpatient lol but thanks!

I have a problem with my fan turning on so I figured I'll check to see if it works. So I manually jumped it to the battery and it works. So I'm trying to figure out if its the sensor or the relay.

*How do you jump the fan switch so that it automatically turns on? Usually on my civic I would just take a paper clip, fold it in half and stick it into the two pins and turn the car on. But for the toyota it looks like theres only 1 pin for the fan connector.

btw the fan does turn on only when I turn on the a/c. Is that weird? It turns on and then turns off then like 30 secs later it turns back on.

Please help me! Thanks in advance

[562daybid]

I also tried searching the forums by using keywords like: test fan or radiator fan or cooling problems but its hard finding a particular problem.

[NWMO 95 Prizm Lsi]

562,

If I'm not mistaken, the fan should run when the wire is diconnected from the sending unit. If it doesn't kick on imediately, give it a minute.

Chris

[562daybid]

Originally Posted by NWMO 95 Prizm Lsi

562,

If I'm not mistaken, the fan should run when the wire is diconnected from the sending unit. If it doesn't kick on imediately, give it a minute.

Chris

Really? thats a pretty cool feature from Toyota. I was gonna get a wire and stick it into the fan switch harness and ground the other end to the chasis or something to see if the fan turns on. Gotta try this tomorrow. Thanks and wish me luck!

[ganda1f]

Originally Posted by 562daybid

btw the fan does turn on only when I turn on the a/c. Is that weird? It turns on and then turns off then like 30 secs later it turns back on.

If you have AC you will have two fans. One in front of the condenser, then comes the radiator, then the radiator fan and then the engine. Whenever the AC compressor clutch engages, both the condenser and radiator fans are activated.
Then the radiator fan also turns on whenever the engine coolant gets hot enough.

[562daybid]

Well I took of the fan switch and turn the car on and it worked! So now I can eliminate the culprit:

Fan works
Relay works
Harness works





Only 2 culprits left:
Thermostat
Fan sensor

What do you guys think it is? The top hose is super hot, the bottom hose is a little hot and there's a little bit of smoke coming from my radiator.



*What is bothering me is how I can drive around the block for around 5 mins and not hear the fan turn on. The temperature gauge is a little less than half way. Is that unusual? or is the engine coolant temperature just not hot enough to activate the fan switch?

[NWMO 95 Prizm Lsi]

562,

I may have missed it, but I don't see where you ever stated a problem? My temp guage is a little different, but runs very near where yours is, just below half way. I almost never hear my fan run, only noticed a few times and then not for long. As long as the car is running cool, I would think you are good to go.

Chris

[562daybid]

Originally Posted by NWMO 95 Prizm Lsi

562,

I may have missed it, but I don't see where you ever stated a problem? My temp guage is a little different, but runs very near where yours is, just below half way. I almost never hear my fan run, only noticed a few times and then not for long. As long as the car is running cool, I would think you are good to go.

Chris

Sorry I didn't make it clear. I am having trouble with my fan not turning on when its suppose to turn on. I am just concerned because I idle the car for like 20 mins, take it for a drive and come back to see if the fan turns on but it doesn't and my temperature gauge is normal. I was just wondering if this was possible for the temperature to stay down even if the fan isn't turning on.

[ganda1f]

The fan switch is located in the outlet from the radiator. Coolant goes into the radiator at the top and comes out cooled at the bottom. If the *cooled* water is hot enough it will trigger the fan switch. Meaning that the radiator fan will not turn on until the bottom hose from the radiator is hot enough.

The temperature sending unit for the gauge on the instrument cluster is located at the pipe going from water pump to cylinder head and thus shows temperature of the coolant circulating in the engine.

If your bottom radiator hose never gets hot than perhaps the radiator is seriously clogged? Do you have a lot of coolant going into the overflow bottle when it gets hot? Due to pressure build-up. Is the top hose hard due to high coolant pressure?