No! If a fuse is blown then there will be NO power to the unit which is the purpose of the fuse. If there is a wire directly to the battery then you might have an amp hooked up the the stereo because a regular head unit does not require a direct hookup to the battery. You have the fan hooked up right so leave it alone, what I would do is UNdo whatever you did to the radio and rewire it they way I suggested ( the constant HOT to a fuse that stays hot regardless of the ignition switch position and the swithed wire to a switched fuse meaning it gets hot only when the key is turned on.

 

Got ya, that didn't sound right to me either, too tired last night to think straight. It was HOT in Texas yesterdaywhenI putthouse things in.102* and no problems with overheating!

There isn't an amp in the truck, but I wouldn't be shocked at all if the guys at Circuit City got lazy with the stereo install and just ran straight to the battery for the hook up, rather than crawl under the dash.

I'll have to pull the stereo to see what's been done. Might have to take it back to Circuit City, as I don't have the wiring diagram for the stereo.

 

OK everyone,

I have isolated the problem:. ME , but I need help fixing that. (insert commentary here)

The + wire from the keyed ignitionsource was indeed spliced into a keyed ignition wire. However, using a splicer didn't actually break the circuit as there is acircular run from the + battery terminal to the keyed igintion switchthen back down to the controller. Here's a link to a very similar unit'sdiagram, for all purposesit will function exactly the same:
http://www.flex-a-lite.com/auto/31149-998421.pdf

WhatI need help with is why are you feeding a constant source (+ small wire from battery) to a switched ignition source (the key) and back to the controller? Doesn't that just circumvent the ignition by feeding it constant power from the battery? I would think you would run a single wire from the ignition source to the controller, just like the A/C clutchcontrol is shown.

As stated earlier, when I have the fans wired up as illustrated, the stereo stays on after I remove the key from the ignition,but when I disconnect the fan system from the battery + terminal, the stereo works again with the key. Is it possible that the stereo installer just happened to pick the same wire to tap, or am I really just feeding juice to the whole electrical system?

Any help with this would be greatly appreciated as it's been kicking my butt for 2 days now, and I'm getting tired of constantly disconnecting the battery.

 

From what I see on your link they use the constant (+) for the controler to shut off the fan after system has reach a preset temp on the temp controler. And the keyed (+) for normal operation while engine is running. Do you have a temp control in the curcuit If not disconnect the constant power wire, but if you do set it to turn fan off at a desired temp

 

Oyur stero plays also because it is feeding power to your stero through the fan setup till engine temp has dropped to a point that temp control says to shut everything down

 

I do have a thermo hooked up to the radiator, but on the newer controller part #31165 there are two separate pins for the thermo. Since the fan controller is getting juice from the thick red wire, the thermo should still work,right?The controlleralso has an adjustment screw that lets me control the on/off temps on the fans. I'm not overly worried about the fans running after I shut down the engine, because the clutch fan never ran to col the radiator, and the water pump's already off as well, so the coolant isn't leaving the engine block anyway.

I just don't get why there's a line running from the pos battery to the ignition source.And I really don't get why the radio stays on.

 

BTW, just checkedto be sure the radio stays on after fans quit on shutdown. [&:]

 

ok this post really confused me and im not sure what stage you are at right now.. but ill start from square 1...

thing of your fan controller as a relay,, on top of that.. your fan controller (elec tstat) isnt tough enough to feed the fan directly.. too much amperage.. so you need to ue the fan controller to switch a 30/40 bosche style relay.. thing of a relay as a electrically actuated switch..

easiest way to explain it is.. the fan gets its on/off power from the 30/40 relay.. and to controll that relay .. you wire it to the thermo t-stat. and to controll the stat .. you wire it to a switched 12V scource.. this is why

DC motors, under free spin,, turn into generators,, back feeding your system, witchis bad.. the relay (30/40 bosche) breaks the circuit so when the fans arnt needed, its a broken circuit and no power can come back to the entire truck..

so now you have a fan wired to a relay.. but how do you activate that relay? well you do this by the stat, and this stat will send a 12V signal to the relay to tell the coils to close or open the arm inside the relay.. when the stat feels that the rad. is getting 180 deg (or whatever parameter you have it set to ) the relay inside the stat will close, send this signal to the 30/40 relay,, inturn switching on the fan...

NOW,, you have to get power to the stat for it to actually work..and this is where your switched scource comes into play.. instead of running the hot lead from the stat to the battery,, all you wire to it is a ground , a switched 12V and the signal wire going to the 30/40 relay.. this is so.. if you think about it.. the stat is only active when you have the key turned,, and this will only activate the 30/40 relay,, and then this will only activate the fan.

if you have two fans.. you need to double everyhting and everything needs to be its own seperate circuit

you should mull this over.. think of the questions you need to ask.. and repost.. i gotta run.. gonna be late for the movies.. ill be back in about 2 hours..

sorry i couldnt give you any wiring diagrams.. wife is hollering.. you can search for these diagrams and post them an di can edit them for your needs..

this wiring method for fans for OUR trucks is the most easiest,, effeicent, and longest lasting..

hope th is helps!!!

i got a really good source for a 12V switched but i cant remember whitch factory relay it is,, neither what leg i have it ran off of...

ill get more info later

sorry for the crappy spelling.. im typing like 10000 milioon words a minuite!

c-ya

 

I agree with shotts method of doing the hookup as it is easy and eliminates the power draw when everything is shut off. Since you are not worried about having the fans on when the engine is shut off I would go with his setup for wiring

 

Hey all.

I think I have it fixed.

What I did was this. I cut the thin red wire from the pos battery terminal to the splice into thekeyed ignition source (in this case the blue wire from the wiper motors. 25amp fuse, felt better about using that one). I ran the second half of the thin wire from the wiper splice to the controller. The radio now turns off with the key. The fans also both run on A/C startup, and thermostat control individually. The fans run about 30 seconds and shutdown as well after the key is out, and the DAMN RADIO GOES OFF!

This was my reasoning:

Thewhole unit's getting power from the Large Red and Black wires running to the Battery. The thin red one running to the keyed ignition source is redundant for powering the controller because it's already got juice. This extra cord was just feeding juice directly from the battery to the wipers and circumventing the key, which is why they started wiping when I spliced into the wrong wire yesterday, even though the keys weren't in the ignition (also somehow feeding the radio). Just like the AC controller only needs one wire to operate, theignition controller should only need one too. I really think that extra small wire running from posbattery to the ignition source should begone, at least for my application.

I will go get a bosche relay though, as I don't want the freewheeling fan to feedback current into the system. The real test will be whether or not the battery's dead tomorrow morning. If that happens, I'll be back.
Thanks for everybody's help, it really did make me think in different directionsto troubleshoot this. Shott, I hope you didn't get in trouble with the Mrs.!

On an unrelated note; Fastman TB came today. Took off the old one and saw oil in the plenum pan. Well, that's next month's fix. Guess the programmer and headers are moving down the line for Oct. and Nov. Gotta print Steve's guide out and go over it a few times.