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Huaraches
03-04-2015, 05:56 AM
not sure why it just turns on when i turn the key to the on position (car is not running). only to turn it of is by unplugging it from the plug that actually connects to the fan. radiator is empty but that wouldnt cause it to turn on would it? i will check wire diagrams to trace the wires. but just decided to ask to see if any thing else can cause it,

Shadowlife25
03-04-2015, 06:04 PM
not sure why it just turns on when i turn the key to the on position, radiator is empty but that wouldnt cause it to turn on would it?

It sure would. It is working properly. :)

Huaraches
03-04-2015, 06:06 PM
Ok so after i add coolant it shouldn't do that. Untill it reaches the temp ?

Shadowlife25
03-04-2015, 06:13 PM
Exactly. That is a fail-safe feature.

Huaraches
03-04-2015, 06:17 PM
Thanks i thought i did something wrong on the harness but idk how if i never messed with assesories

alltracman78
03-04-2015, 11:24 PM
The fan doesn't care how full the radiator is, it only cares about the radiator temp.

You probably did mess something up on the harness. Did you remove the AC by any chance? Is the AC pressure switch hooked up?

Shadowlife25
03-05-2015, 12:37 AM
Jeremy, you are right. My bad on this. It is temp based. I just forgot because I remember the unplug to run full tilt thing.

Again, apologies to all.

Huaraches
03-05-2015, 01:13 AM
Ac i removed that

Huaraches
03-05-2015, 05:25 AM
You probably did mess something up on the harness. Did you remove the AC by any chance? Is the AC pressure switch hooked up?

ur right my bad, i did delete it and no ac wire is hooked up is there a fix ?

alltracman78
03-06-2015, 01:12 AM
Jump the switch.


Jeremy, you are right. My bad on this. It is temp based. I just forgot because I remember the unplug to run full tilt thing.

Again, apologies to all.

Not accepted. I think you did it on purpose.

Huaraches
03-06-2015, 01:13 AM
Hmmm jump the ac switch ?

Shadowlife25
03-06-2015, 02:42 AM
Not accepted. I think you did it on purpose.

LOL! :D You slay me bro. :P

underscore
03-06-2015, 08:54 PM
I didn't have to do anything to the wiring when I ditched my AC, just make sure you didn't accidentally break one of the wires going to the rad temp switch or the temp switch itself when you removed the AC.

Hiko
03-07-2015, 03:57 AM
Hmmm jump the ac switch ?

Yup, I deleted the AC and had the same problem as you. Trace the wires to the ac pressure switch (IIRC) and jump the two side pins on the plug. Plug will be by firewall on the passenger side. Let me know if you can't find it in the diagram and I'll take a pic tomorrow of what I did and post it for you.

Huaraches
03-07-2015, 04:10 AM
Does it connect to to a vsv type thing lol

Hiko
03-07-2015, 04:13 AM
You're lucky I'm bored :D

http://www.celicatech.com/gallery/files/3/2/0/hereyago.png

Huaraches
03-07-2015, 04:31 AM
Jajaja thanks

Huaraches
03-07-2015, 04:31 AM
Wel hey atleast im trying to keep the forums alive :P

Hiko
03-07-2015, 04:34 AM
Jajaja thanks

No prob :)


Wel hey atleast im trying to keep the forums alive :P

It's slow these days, but the knowledge is still around...

Huaraches
03-07-2015, 04:53 AM
Thats a good thing for this forum was the most useful for my swap, but the motor i got was bad, shady sellers :(

Murgatroy
03-07-2015, 05:59 AM
How do you know the motor is bad?

Huaraches
03-07-2015, 06:03 AM
Turned it on and shuts of. Checked compression and seems low although this will get out of topic its cyl 1-4 155, 145,70,130 my timming is on spot and u hear squeaking maybe metal rubbing metal and i did crank without starting so it can get oil on the parts.

Huaraches
03-07-2015, 06:03 AM
Before starting* *

klapa
03-20-2015, 03:52 AM
I didn't have to do anything to the wiring when I ditched my AC, just make sure you didn't accidentally break one of the wires going to the rad temp switch or the temp switch itself when you removed the AC.

I had strange problems with my rad fan - problems that were actually simple once I read the BGB electrical section and saw the switch between the radiator temperature and the AC system pressure switches for rad fan control.

My problem was - as usual - my car would overheat at times. Most times in traffic - but sometimes on the highway.

This kept going on and I would check things in the evening when I got home - by running the car at idle with the AC on full blast - thinking this was the worst cooling scenario. Yet - it would not overheat, and both fans were running, I had a relatively new radiator, and the cooling system pressure and rad cap were tested good.

I finally noticed that the problem would only appear if my AC was NOT on - which at first seemed to make no sense - until I read the BGB electrical section about rad fan control.

For my car, a 92 4AFE Celica, the rad fan is controlled by the temp sensor in the thermostat housing UNLESS the AC is on - else it is controlled by the AC system pressure switches.

So my problem was simply that the temp sensor in the thermostat housing was no good, but due to the fact that it was in the summer that this happened, the problem was masked by the fact that everything was fine if I had the AC on.

I guess I should have just checked the temp sensor with a meter - it was only after reading the BGB that I figured out that it had to be the temp sensor - and that was the problem - replacing the switch solved the overheating.