If your 4WD switch looks like this AUTO, 4HI, 4LO then...

[Blee1099]

Is in a pack of wiring, it's a brown wire about 14 guage or so.. it's thicker than the rest..

 

[briwayjones]

Ok I'm getting really parnoid now. I pulled up the trim by the door. There is only one solid brown there that I see. It's bigger than some of the wires, but the same size as a lot of the other wires. There is a black wire there also that is a lot bigger than all of the other wires. Is it the brown one, or is it the black one and just a different color in a 2000 Explorer or something?

Whoops didn't see your previous post. The brown wire is about 14gauge or so, but a lot of the others are about that also. The black wire has to be about 8gauge or so.

 

[Blee1099]

You might have to dig through some of the bundle of wiring to find it.

 

[JDraper]

FYI, the brown wire (and the bundle that it's in)in my truck is directly under the driver's seat and goes from the door sill to a grommet in the center of the floor pan on the driver's side. From that point, it goes under the truck to the Xfer case . I removed my front seat to access the wire more easily.

 

[briwayjones]

Ok I accessed the wire in the bundle under the door trim. It seems to be the right wire because the 4wd will affect how the switch works. I'm having trouble getting it wired right. If the switch is wired right and the switch is in the off position should the 4wd light come on when you engage the knob? If it should come on the 4wd just won't work? I think I had it wired right at one point because with the switch in the on position and the 4wd engaged the LED on the switch would come on, but if I turned the 4wd knob off the LED would turn off. Is that correct? Also I want to make sure of something. There are two wires that come off of the back of the cigarette ligther. One that should be the hot wire that goes to the center and a black wire that connects to the side, that black wire is a black wire right? I'm using that one to ground my switch.

Thanks guys.

 

[Blee1099]

Originally posted by briwayjones
Ok I accessed the wire in the bundle under the door trim. It seems to be the right wire because the 4wd will affect how the switch works. I'm having trouble getting it wired right. If the switch is wired right and the switch is in the off position should the 4wd light come on when you engage the knob? If it should come on the 4wd just won't work? I think I had it wired right at one point because with the switch in the on position and the 4wd engaged the LED on the switch would come on, but if I turned the 4wd knob off the LED would turn off. Is that correct? Also I want to make sure of something. There are two wires that come off of the back of the cigarette ligther. One that should be the hot wire that goes to the center and a black wire that connects to the side, that black wire is a black wire right? I'm using that one to ground my switch.

Thanks guys.

Yup the 4WD light will come on when your in HI or LOW. The mod just cuts the power of the torque on demand clutch for your front wheels. With the switch turn off, you can put it in 2HI, 2LOW or with it on, you get auto 4, 4 hi, 4low. Just make sure you label on/off correctly. If your using a rocker switch with a LED, yes hook up the ground wire to something that's grounded. There's plenty of grounding spots on the X.

 

[briwayjones]

Ok so whether the switch is on or off the 4WD light will come on? 2WD Lo, how does that work? The 4WD switch in Lo with the 2WD drive switch engaged? It engages the lower gearing but not the 4WD?

 

[Blee1099]

Originally posted by briwayjones
Ok so whether the switch is on or off the 4WD light will come on? 2WD Lo, how does that work? The 4WD switch in Lo with the 2WD drive switch engaged? It engages the lower gearing but not the 4WD?

All right let me explain this, when you switch into 4HI or 4LO w/o doing the modification your instrument panel lights up. By putting in this switch in, you are essentially cutting off power to the front wheels when your are in 4HI/LO/Auto at your own discretion. The computer still thinks your in 4WD hence the instrument panel lights up even though you have cut the power to the front wheels. 2LO is pretty much 4LO w/o the front wheels engaged.

 

[briwayjones]

Ok thanks, that's what I thought.

 

[briwayjones]

Thanks for being patient guys. I got it installed and working. Thanks a lot.

 

[briwayjones]

An update. I ended up using a 25amp switch and so far it's holding up. So 25 might be the minimum you can use. Someone said it burned up a 20amp switch.

 

[Blee1099]

Originally posted by briwayjones
An update. I ended up using a 25amp switch and so far it's holding up. So 25 might be the minimum you can use. Someone said it burned up a 20amp switch.

I need to hook up my Fluke multimeter to do the TOD clutch wire.. I think 20 amps is definately over doing it but I'm not 100% sure.

 

[Opera House]

Reality check

On my 4405 the coil resistance measures 5.5 ohms which matches up with the measured 2.1A current flow in 4WD. Interesting to note that in AUTO and the PARK position the current is a little over 0.3A to provide a little power to the front. I use a cute little 5A rocker switch that press fits into a little rectangular hole I made in the panel below the steering wheel. No need for some monster 25A switch or relay.

 

[briwayjones]

This is weird these conflicting results, because people reported burning up 20A and smaller switches.

 

[zzimzimma]

Ok..I wanna do this mod...Can someone please explain how to wire a relay w/ a switch for this setup? Thanks

 

[Billy177]

just run a relay and a switch to the thick brown wire under the drivers seat. directions should come with the relay

 

[zzimzimma]

I understand where I need to run the relay and switch to. My question what pins on the relay go to what?

The standard bosch relay has pins labled 87, 87a, 30..etc. I'm just wondering where the brown wires attach to. once I cut the brown in half, I'll have 2 wires. Which pins do I connect them to? I know the relay will get a ground. Where does the switch get hooked in to this? Do i need to apply a 12 volt power supply to the relay?

 

[Billy177]

it will say what wire goes to what pin on the relay packaging but yes you will need a switched 12volt sorce to turn on the relay

 

[Opera House]

Relay Connections
All automotive relays have a schematic printed on them and the pins are numbered on the base. It may require a magnifier and optimal lighting to see them. When the relay is powered, the (87) NO or Normally Open relay contact connects with the (30) C or Common contact. Some relays do not have the center pin (87a) NC or Normally Closed contact since this has no use in many applications, Pins are designated by the state when no power is applied. The coil of the relay are pins (85) and (86). These are on the outside edge of the case and face in the same direction. Coil resistance is typically about 70 ohms.

You do not need a relay because the current is under 3A and this is handled easily by most switches.

 

[Billy177]

not true it may be three amps in auto however in high and low it is a much higher amperage. why do you think they used the thicker wire