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Howler_GT
05-23-2009, 08:27 PM
Just about everyone at one time or another wishes they could kick in the factory electric cooling fan to take the edge off the temp gauge.

Today, while snooping (I call it RESEARCH) around the engine bay of Lil Red, and some poking and prodding. I came up with a CHEAP and easy way to install a trip switch for the fan.

I know...I know... NOT another switch thread.
But this is different. As it looks like it belongs and if done properly, this mod is invisible... except to YOU.

Lil Red (My 94 Sport) uses TWO of the FOUR factory switches below the speedometer.

<FOG> <DEFROST> (STEERING WHEEL) <TRANS> <R.WIPER>

Lil Red has DEFROST and R. WIPER. There are TWO unused ports (covered up)

Since the wire to the glass has become undone in the rear and I DO NOT want to <expletive> with it. (Me and glass do not agree)

This little write-up will deal with using the existing switch. BUT a second switch and connector can be grafted into the wiring and used.

No pics right now but if the weather holds up tomorrow....

FAN WIRE: Between the airbox and PCM/ECU/ECM there is a pair of wires that connect to the electric fan. GREEN & BLACK. From the fan connector to where they run into the main wiring is about 12-13". Pull them from thier "sleeve". Airbox removal helps to give enough room.

GREEN is + /BLACK is -

Use an 18ga CRIMP Splice connector (piggy-back connector) to attach a 5' length of BLACK 18ga wire to the GREEN (+) wire. Electrical tape it to give it some protection.
Push wires back down where they belong and re-install the airbox if removed.

From driver's floor: Drill a small hole in firewall between the brake assembly and the fusebox. Go LOW this will help avoid the brake booster and make fishing the wire easier. Use a grommet for the firewall. Push wire into passenger compartment.

DASH: Remove dash bezel. Make sure you get ALL the screws. One at light switch, one at lighter and two in speedometer area.

SWITCH: I will use the left side.
One screw to remove the switch housing.
Pull housing out.

Another switch can be used. If you use another stock DEFROST switch (make sure you get connector too) main power can be brought up from fusebox (use a 30a fuse)

DEFROST has 4 wires. 2 for indicator light and two for defroster.

For our purposes, we will use the BLACK w/Red stripe. I just used another crimp splice connector. Since the original wire isn't connected to anything in the rear...Im not worried about the integrity of the wire.

Make sure to trim the wire down to an appropiate length before attaching
Put everything back together.

Fire up the engine. When temp hits YOUR desired "hot enough" temperature.
Click the switch. Fan turns on for 5-6min then shuts down. Enough time to take the edge off.
In my case, since I am basically replacing what the original switch activates, it acts EXACTLY like the original.
Light illuminates and all.

ONLY side-effect: When A/C is turned on...light on switch illuminates.

After its all buttoned up. The mod basically becomes invisible.

N1TZU
05-24-2009, 03:11 PM
Very cool mod for the jeep Howler...Thank you...

Voldemort
05-24-2009, 03:13 PM
Pics Please

Howler_GT
05-24-2009, 03:54 PM
ONLY DEFROSTER ON THIS SIDE:

http://img22.imageshack.us/img22/7629/0000007k.jpg


GREEN wire piggy-backed:

http://img22.imageshack.us/img22/6301/0000004wkc.jpg

Wire thru firewall:

engine bay--

http://img22.imageshack.us/img22/7946/0000006b.jpg

under dash--

http://img22.imageshack.us/img22/1849/0001qda.jpg


What it looks like AFTER the mod:

http://img22.imageshack.us/img22/7629/0000007k.jpg



I actually timed the fan cycle today. Runs for approx 8min before automatic shut off.

Mudderoy
05-24-2009, 06:31 PM
Yes this is a mod I am going to do. I bet it is different for a 97+ though. :(

Howler_GT
05-24-2009, 07:29 PM
One thing I must add:

If you are going to be using the stock DEFROSTER switch for the fan, and do not intend to use the rear defroster. Clip the wire.
Otherwise when you hit the switch the only thing that will happen is a blowing of a 30a fuse.

Not sure how different it would be except the location and shape of switch itself.
MAYBE the wire color, IDK

Voldemort
05-24-2009, 09:44 PM
One thing I must add:

If you are going to be using the stock DEFROSTER switch for the fan, and do not intend to use the rear defroster. Clip the wire.
Otherwise when you hit the switch the only thing that will happen is a blowing of a 30a fuse.

Not sure how different it would be except the location and shape of switch itself.
MAYBE the wire color, IDK
Ok so all you have to do i piggy back off the green wire and splice it to the ? wire from the defrost switch? And cut ? wire to the fuse box?

Howler_GT
05-25-2009, 12:51 AM
Piggy-back GREEN wire underhood.


If using stock DEFROST switch but not keeping defroster...
Clip and attach to BLACK w/Red Stripe wire coming OUT of switch.