BWM Brown Wire Mod 3rd Gen

[17fordguy]

this bundle of wire is on the drive side of the engine it runs up from the bottom of the vehicle and across the fire wall and in to the pcm i think i counted about 2 brown wires in this bundle the i identified the proper wire by setting my voltage test to the continuity test and atathed one lead to the brown wire at the plug on the transfer case and the other lead i just tested the wires until i got a beep from the voltage tester.

note this is only on the 2004

 

[JCUZ]

this bundle of wire is on the drive side of the engine it runs up from the bottom of the vehicle and across the fire wall and in to the pcm i think i counted about 2 brown wires in this bundle the i identified the proper wire by setting my voltage test to the continuity test and atathed one lead to the brown wire at the plug on the transfer case and the other lead i just tested the wires until i got a beep from the voltage tester.

note this is only on the 2004

And only on LHD Explorers - on ours, that loom is on the passenger side of the truck.

 

[17fordguy]

yeah it eems real weird to me oneford would do it different for one year truck than all others

 

[JCUZ]

yeah it eems real weird to me oneford would do it different for one year truck than all others

It's not a year thing - ours are Right hand drive.

 

[17fordguy]

i was actualy refeing to y would the integrate the 4wd module into the pcm on only the 04

 

[Curtis]

Here is a question....


A relay can be wired to turn things off as well as turn things on. When a switch is activated, the relay will open. Right?

If that's true, has anyone poked around behind the 4x4 high switch to see if power is there when its pushed? If that's the case, you could use that button to activate the relay which will in turn disconnect the brown wire?

But then when I think about it, you'd have to hit the 4x4 high button to open the relay again...

I dunno.. just rambling here... trying to think of a way to utilize the factory switches...

 

[ktford]

if you read what JCUZ said earlier you don't need a relay
Scotty

 

[JCUZ]

Here is a question....


A relay can be wired to turn things off as well as turn things on. When a switch is activated, the relay will open. Right?

If that's true, has anyone poked around behind the 4x4 high switch to see if power is there when its pushed? If that's the case, you could use that button to activate the relay which will in turn disconnect the brown wire?

But then when I think about it, you'd have to hit the 4x4 high button to open the relay again...

I dunno.. just rambling here... trying to think of a way to utilize the factory switches...

Scotty is right - and I've said it before, you don't need a relay - in fact a relay is ineffective, as the voltage to a 12V relay is not enough to fully open the relay, as it's only ever going to get max 5v to it.

Also, with this solution, how will that work with Auto 4WD? That would mean you'd only ever have a 2WD option when you selected 4WD, and you only select 4WD High when you really need it. This mod is only really aimed at day to day street driving, when you may consider that you don't need the extra safety that 4WD brings. Or the drag strip.

 

[jutgin]

I still want to know why on my 2002 the brown wire mod didn't work? I cut the brown wire indicated on the start of this thread and it did not work. Everything still engaged. Confusing.

 

[JCUZ]

I still want to know why on my 2002 the brown wire mod didn't work? I cut the brown wire indicated on the start of this thread and it did not work. Everything still engaged. Confusing.

How do you know it engaged? What testing have you done to verify this? Are you 100% sure you cut the right wire? If you think you did, the 4WD High or Low will still light up on the dash, but that doesn't mean it's actually in 4WD.

 

[jutgin]

No - the light still lights up, as the ECU/PCM still thinks it has sent a signal to the transfer case - but because you have intercepted that signal by turning the switch off, you have effectively cut that connection. The 4x4 (High/Low) lights still light up, but the transfer case can't engage, therefore you are in 2WD mode.

The only way to tell if 4WD has actually engaged or not is to have what I have - this is an additional small LED light that is powered from the brown wire (but at the transfer case side of the switch). So, when the switch is on, this light lights up all the time, as the transfer case always gets around 2volts constant power. When 4WD is actually activated (either in auto mode, or by selecting High or Low manually), the light gets brighter so I know 4WD is on. When the switch is turned off, the light is not lit at all, and so I know that it is in 2WD mode, as the transfer case is not receiving any power signals at all.

I might get some photos later to show the difference between on in 4WD auto mode, on when engaged in 4WD, and off.

Thanks that is what I was looking for. I guess I was assuming that if I cut that wire then hit the 4lo button it should not light up on the dash. But I need to test this again and see if when it's cut if I can actually engage the 4lo/hi. I guess I could also try and roast the tires but I'm gonna try the manual way first. But I'm sure if it wont engage manually it shouldnt engage automatically either. Ok I get to play with it again! Thanks for the help!

 

[jutgin]

It works! It works!!!!!!!!!!
WOOOOOOHOOOOOOOOOOO

Thanks so much. I love having the option. And I hope it saves some gas cause I'm going to Michigan soon, about 900 miles one way!!
Thanks again!

 

[ktford]

it feels good to see a kid smiling, LOL
Scotty

 

[jutgin]

Oh I wish I was a kid again, I just hit 30. ONE WORD---RESPONSIBILITY!!

Thats why I love my truck projects, makes me feel that way again!

 

[EXPLORER04]

for those of you who have the bwm on a 4.0 04, is the bw in the top or bottom wire harness that runs behind the engine?

 

[IZwack]

I mentioned this in the 2nd gen BWM thread but just to make sure (since it applies to the 3rd genners too), be aware that doing burnouts with the BWM comes with consequences -- sometimes very costly drivetrain consequences.

Akay back to your regg.. regggg. reggggulurly scheduled program

 

[Black92LX]

I mentioned this in the 2nd gen BWM thread but just to make sure (since it applies to the 3rd genners too), be aware that doing burnouts with the BWM comes with consequences -- sometimes very costly drivetrain consequences.

Akay back to your regg.. regggg. reggggulurly scheduled program

As with all Drive trains it's not good for any vehicle to do burn outs.

 

[Black92LX]

just a standard 12V 10Amp switch with each side of the switch going to the cut wires from the transfer case will do the trick.

does it matter which end of the wire goes to the power or the load on the switch?? Since you are just breaking the circuit I assume not but will it affect the functioning of the light.
As you stated earlier it will be dim when in 2wd and bright when 4x4 is engaged.

 

[Black92LX]

Brown Wire Mod is done!!!!!

I mounted my switch in the top of the sunglasses holder in the overhead console. Don' even know anything is done till you open the sunglass holder!!

Monday will be my mpg test. doubt i gain anything but I am glad to be able to choose 2wd and 2wheel low now!

 

[BigBlackMerk]

a friend of mine has a 97 x and all he did to make it 2wd was pull out the fuse for the 4wd. at lease thats what he told me. is that posible?