Whats up guys? I have an 89 Turbo and my aux fans are always on. When i turn the car to the "ON" position they turn on. It's quite annoying and likely a drain on my battery. Previous owner installed a Fluidyne radiator and im scratching my head as to why those fans are always on. Any input is greatly appreciated even if its a shot in the dark. I am not good with wiring, in fact i hate it. :1zhelp:
Auxillary fans always on
- Thread starter DBN
- Start date
Because they are getting power and ground when the key is on.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=144
And the page before. Do you have the EWD for your year?
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=144
And the page before. Do you have the EWD for your year?
The fans power on when a ground is placed on the relays to the fans completing the circuit.
Two sources of ground at least on my 89 auto trans car are the high pressure ac switch and the temp switch #3 on the water outlet. Here is the link to the AC tsrm where you can see how the switch 22 and switch 28 work. I would disconnect the plug that goes to the temp switch on the water outlet and turn the key to on. If the fans still turn on you can disconnect the high pressure ac switch. If they fans still turn on.....???
My point being one of those two switches might be closed and providing ground 24/7.
Two sources of ground at least on my 89 auto trans car are the high pressure ac switch and the temp switch #3 on the water outlet. Here is the link to the AC tsrm where you can see how the switch 22 and switch 28 work. I would disconnect the plug that goes to the temp switch on the water outlet and turn the key to on. If the fans still turn on you can disconnect the high pressure ac switch. If they fans still turn on.....???
My point being one of those two switches might be closed and providing ground 24/7.
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^He's right. When a sensor (most probably the waterneck temp sensor) goes faulty they will make ground (failsafe by toyota) and cause the fans to always turn on. So check the sensors first.