ok so i figured out how to have pwm fans without the expensive corvette controller with the impossible to find plug

*****disclaimer ******

this works for me it may or may not work for you
most cooling fans can pull a good amount of current
(enough to start a fire if something goes wrong )
make sure the module/relay can support your fan and please insure everything is wired correctly and fused properly
I'm not responsible for what you do to your vehicle/self/grandmother's garage

*****end disclaimer*****

ok so i have been experimenting with various cooling fan control setups for the jeep i'm building (03 wrangler stretched 15" with a 09 4.8/gt45/e85/4l80e/circle d billet converter)

the 09 4.8 runs on a 09 e38 ecm/t42 tcm (with a van calibration)

i wanted my cooling fans to be pwm but i didn't want to spend the money on the corvette module / plug

i have successfully used a 05 caravan/town & country fan controller (04-06 chrysler mini vans used pwm to control the fans from 30% to 100%

the controller is simple and widely available cheap (they even give you a plug most of the time )

although i recommend getting one directly from the chrysler dealer (for reliability) i don't think they come with a plug

i grabbed mine from a local salvage yard as i was unwilling to wait

here is the link for the dorman one on amazon

$29.61 with free 2 day shipping (if you are a prime member)

the factory wire colors are as follows

orange/red fused 12v+ (had a 40amp fuse from the factory)

dark blue/dark green output to fan (12v+)

dark blue/violet control wire (goes to x1 pin 58 on a e38 ecm

black/dark green ground

for mounting the module has one locating peg and a hole for a hold down bolt
(i drilled a 5/16 hole for the peg and used a self tapping bolt to secure mine to the fender

the efan i'm using on my jeep is from a 02 ford escort which uses a 40a fuse also

after setting up my tune (via efilive) by turning the fan option to pwm electric and setting of the % table (i was careful not set a % lower than 30% as according to the chrysler service manual that is as low as the minivan ecm goes) and i didn't want the burnup the module by making it work outside of its design limits

i was disappointed after initially running the fan test via a tech 2 (scanning as an 09 corvette) as the fan was kicking on and off repeatedly (starting slow and going faster) but that must be how the test is performed as when the engine was warmed up the fans kicked on right as they should and slowly increased in % as the ect went up

i consider it experimental but i'm gonna be driving this thing shortly and so far it has just worked like it is supposed to

so there a gen 4 pwm fan controller for under $30 including the connector

if anybody wants to donate to my alcohol fund so i can drink to forget the 85 pages of service manuals,wiring schematics,and pwm operation technical crap i've read recently then my paypal is scott (dot) elenbaas (at) gmail (dot) com

enjoy your pwm cooling fans!

 

How about more pictures of the stretched jeep?

 

Cool find and a nice way around the Corvette tax. Thanks for sharing the research.

One question: all the pictures I see show four wires and only two colours. What is the pin out on the module? It's difficult to say from your picture but it appears to be (tab up, facing away): Power, fan, ground, signal. Is that correct?

 

that is correct

pin 1 is fused power

pin 2 is output to fan

pin 3 ground

pin 4 is the control wire

 

here are a few

 

Cool, thanks a ton.

Nice jeep, now you have enough power to pull those hills and get over those rocks.

 

Great writeup. I just sent you a little booze money via PayPal...

So if I was running dual fans, I would need to run two controllers?

Right now I have a twin Spal set-up with the GMPP e67 controller and harness. The fans are wired through a relay and it all works OK, but when the fans kick on it is pretty abrupt and loud. I would much rather have a more gentle PWM activation.

Andrew

 

Here is another link that discusses this topic in great detail:

http://www.lateral-g.net/forums/showthread.php4?t=40215

Andrew

 

Did you hook up an AC pressure signal too? I would be interested in knowing if that works without having BCM communication on AC (i.e. hardwire/original AC compressor clutch activation with AC pressure signal / ECM driven PWM fan control for AC).

*EDIT* Looks like there is tons of discussion on the AC aspect of this in the LatG thread - Thanks Andrew for sharing that link! http://www.lateral-g.net/forums/showthread.php4?t=40215

 

i didn't as the jeep has no room for a/c (intercooler is a grille space hog)

i may try it in the future as it would be nice to wire it up to a switch/resistor mounted on the dash so you could manually signal the ecm that the pressure is "x" and edit the table so that you can manually override the fan to 100% (or any speed of your choosing

according to the service manual for a 09 vette it should work all the time

"The engine cooling fan is a variable speed fan. The engine control module (ECM) controls the fan speed by sending a pulse width modulated (PWM) signal to the cooling fan control module. The cooling fan control module varies the voltage drop across the cooling fan motor in relation to the pulse width modulated signal.

Cooling fan speed is effected by many different conditions and can be adjusted from 10-90 percent duty cycle , 90 percent is considered high speed fan. When multiple cooling fan speed requests are received, the ECM uses the highest cooling fan speed of all the requests. The ECM commands the fans ON under the following conditions:

• The engine coolant temperature goes above a calibrated amount.

• The engine oil temperature goes above a calibrated amount.

• The A/C pressure reaches a calibrated temperature.

• After the engine is shut OFF, if the engine coolant temperature at key-off is greater than a calibrated amount, or the A/C pressure is greater than a calibrated amount, the cooling fan is set to low speed. The fan will shut OFF if the temperature or pressure drops below a calibrated amount. The fans will shut OFF after 2 minutes, regardless of coolant temperature."

 

Thanks for the added info! Do you know approximately how big that Chrysler fan controller is? It looks like it must be around 3"x3"x?

 

i can measure it but i would say ~ 3"W x 4.5"L(including mounting tab) x 2.5"H

 

thanks,

as far as dual fans go you should be fine as long as they will run on a 40 amp fuse (the factory chrysler application for this controller uses dual fans

i only have 1 fan on my jeep because its a small radiator and that's all that would fit

i hear you on the noisy fans my current driver is a 01 wrangler 4.8/nv3550 with a magnacharger/10lbs of boost using the same radiator and fan as the black one i'm building and the fan noise is very annoying

after i start driving the new one i'm gonna have to sell the old one to repay all the debt cause by the black one you never realize how expensive turbo setups are (even cheap one's) on top of stretching the jeep and swapping the v8 all at once

 

The controller is mounted to the top of the aluminum bumper support with a rivet so be prepared to pop the rivet loose or drill it out. I was able to pop the rivets loose on both that I tried.

 

Just so everyone isnt confused. Someone listed the 4 wires and the ground and signal wire are actually switched. Last pin is ground. 3rd pin is signal.

 

Hi Scotte - How has this thing been working out, long term? I am finally at the stage of wiring my fan and I'm strongly considering following in your footsteps.

Has any one else used this PWM controller?

 

Reviving old Thread, Has anyone tried using this same controller for PWM fuel pump operation ??

 

Also, does anyone know what Hz rate the ecm is sending the PWM

 

If this unit is anything like the C6 fan controller, then it would be slow to react if used as a fuel pump controller.

Andrew

 

Yeah I bought one to use for that purpose. Hooked it up to a homemade pulse generator and it ran my fuel pump just fine. The unit has no internal ramp up or down, it will immediately run the pump at whatever the input PWM duty cycle is.

I haven't tried running this off an ECM, I made my own PWM controller, so I can't help you there.

Some additional info in the post below

https://ls1tech.com/forums/conversio...l#post20033635