quick yes or no question on manual fan switch
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do i really have to use the 1 watt resistors on the low and high speed fan wires so the ses light wont come on??? thanks
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I'm not sure where you got this information from, but if you plan on triggering your fans by running switched power to the fan motor, I would think twice. Those fans pull a decent amount of juice, and you'll need a switch rated for something like 20 amps. A better option is to trigger the relay which controls the fans with a ground.
Either of these methods should set DTC 77 as the PCM tries to figure out why the fans aren't responding normally. This doesn't turn on the SES light as I recall.
An even better method is to use Tunercat or a Hypertech programmer to change the fan on temp. This way your PCM is happy and your temp can stay down. Just don't set the temp too low. I know hypertech has guidelines in the manual for fan on temps. Running your fans all the time is hard on the fans and hard on your alternator.
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just buy the manual fan switch kit from one of the sponsors, it plugs right into the harness on the pass side fenderwell and has a switch to trigger them on/off. Simplest installation I've ever done and works great. Think it's 60 bucks?
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I made my own with a switch from Radio Shack and some wire. I just spliced into the wires for the fan relays. I used the resistors specified in the writeup on Shoebox and haven't had any issues with it throwing codes. One nice thing about having a switch rather than reprogramming the fans is that you can run them even when the car is off, for example to cool it down at the dragstrip after a pass. Even if I had my fans retuned I would still keep the switch in there. Just don't leave them on for too long with the car off.
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It doesn't set 77? Or you meant that it doesn't turn the SES light on?
I've just had bad experience with things like this. I had a car where the ignition switch was bad. I wired up a switch to the starter, but not a momentary. Worked fine until my buddy decided he needed to start the car and then couldn't figure out why the starter wouldn't disengage even after the motor was running...
I've just had bad experience with things like this. I had a car where the ignition switch was bad. I wired up a switch to the starter, but not a momentary. Worked fine until my buddy decided he needed to start the car and then couldn't figure out why the starter wouldn't disengage even after the motor was running...
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#7
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![](http://shbox.com/1/fan_sw_diagram1.jpg)
I'm glad I'm finally on the same page here. If this is the diagram everyone has been looking at from the beginning, that looks like a good way to go. I still like my fans computer controlled, but I'm sitting in traffic and not on a dragstrip.
Incidentally, I think this diagram also answers the original question.