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Discussion Starter · #1 ·
The previous owner put the fans on directly when you turn the ignition on... where I live it tends to get pretty hot outside, on top of that I have a ground effects kit but installed the aftermarket air dam... the thing is I want to know if the fans are on high or are they on low directly... they dont sound too loud as if they were on high and if I drive for more than 30 minutes with the A/C on it goes past 235.. any help is much appreciated, also I ordered the 160 hypertech t-stat, radiator is new, and water pump is good also.. thanks
 

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the easiest way to figure out if your fans are wired for high or low is to unplug one of them. if they dont turn on with one unplugged, they are on low (series wired, low speed). if the other one stays on, they're on high (parallel wiring, high speed)

you'll run into issues with the fans on full time. this isnt because your car will over-cool or whatever.. when you're in motion, the fans are supposed to be disabled, and the air dam is supposed to take over. if the fans stay on at high speed, they actually tend to impede airflow.

are you sure they aren't on full-time because of an error code or something?
 

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Discussion Starter · #3 · (Edited)
The previous owner is a friend of mine and he took it to an electromecanic to put them in series manually.... the car is giving a code, p1641 which could be the fans on directly... thanks a lot for the info.. tomorrow ill do the fan test and come back to let you know..
 

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p1641 would be because of the directly wired fans.

likely the circuit from the ECM to the relay has been interrupted. you can use a resistor or a do-nothing relay and that code will go away. but i'd rather see you hook the fans up properly again, and install a manual fan switch for if it starts to get too hot.
 

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Discussion Starter · #6 ·
Thanks will do!! was thinking if the SLP fan switch is worth the money or just use a regular switch? here's a pic of the car... as you can see the large front lip it has... :eek:
 

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just go ecm controlled, regular toggle switch for the fan, and tune it if you want (probably should, with the 160 degree stat)

very nice car by the way, i hate body kits but that one pulls it off, probably cause its so shiny
 

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Discussion Starter · #8 ·
/thanks a million! one last question... what is the basic configuration of the fans on a 3 relay setup... at what temp do the fans come on? are both on at low?
 

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the relays are just for high/low operation.

the original LT1 had two modes, one fan, or two fans. they decided that sucked. so on a '96 like yours, both fans run all the time, in two modes.

low mode, they're run in series, so they each run at around 6 volts

high mode, they're run in parallel, so they each run at around 12 volts

the ecm is the only thing that controls when the fans come on, and temperature is only ONE factor... there are many others, including certain trouble codes being set, air conditioning parameters, and speed thresholds.

the stock fan turn-on settings are incredibly high. something like 225 degrees for low, and 235 for high, if i remember right.

it's for emissions purposes, mostly. at an idle at a stop light, when the car isn't under any sort of load, they figure if they let it get nice and hot, no harm done, and it'll make less fumes. and they're right. these engines can run damn hot with no problems. it's just not so nice for launch performance..
 

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shbox.com has a wiring diagram on how to hook up the manual fan switch. Nice thing about his wiring is that if fan switch is in the off position, the pcm can still command the fans on when it wants them on.
 
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