BWM Brown Wire Mod 3rd Gen

[Curtis]

went out to day to do this mod but there was no brown wire in the smaller bundle. there was yellow, orange/black, and 2 wires in aluminium. and then was black and red outside of the plastic case. I have 2004 v8 explorer. any ideas???

In 04 the 4x4 Control Module was obsoleted, hence no brown wire in the kickpanel.
For 04, read back though this thread, you have to get it in the engine compartment, I believe on the drivers side of the engine, near the firewall.

 

[Kazer]

thought id chime in since the snow is all gone. i did the bmw somewhere around last september with 70k miles

just wanted to say that i put tcase to work this winter. i hardly ever went into 4wd. i spun my tires at every single chance i could this winter and did my fair share of donuts. ive even had the rear tires spinning at 70+ while the fronts were maybe doin 20. the tcase is working great still, no slippage or anything. i kinda wanted to be the guinea pig for abusing this mod.

so all in all, for me, the transfer case survived one michigan winter so far; HOWEVER, now when i spin my tires in mud or rain, it feels like my one spinning tire(open diff) is hopping violently. ive never had anyone watch it, thats just how it feels behind the wheel.....any ideas on what could be happening?

 

[Limited02]

Wheel hop

 

[Kazer]

ahh alright. i thought whell hop was only with limited slip. is it bad for the truck? i usually let off the gas as soon as it starts

 

[McTuff]

looking at doing the BWM

G-day

I'm looking at doing this mod on my 02 v8 explorer but there seems to but a few differences between the ones in the USA and the ones in Aus .Does anyone have a pic of the wire that you splice into at the back of the T-case as seems to be my only way of tracking this wire down as I have tried all the other places listed to no avail.Any help would be greatly appericated

 

[Xdropped22s]

my guess.. look at your drivers side panel rather than the passenger... Left hand drive... to right hand drive

 

[McTuff]

No joy

I have been too that side of the car with no joy either .

I have found a brown wire at the back of the t-case but it is not of the diameter that I would expect it to be or like the one in the pic shown were it runs thru the door sill.I was looking for a pic from someone who has already cut the wire at the t-case this way I can simply locate the wire by its access point into the t-case itself.

 

[xTOM153x]

P. doggy states that you can put it in 2x4 low by putting it in neutral with the 4x4 turned off then hitting the 4x4 LOW button. Could someone explain to me why it would be beneficial to doing something like that?l Thanks

 

[Curtis]

P. doggy states that you can put it in 2x4 low by putting it in neutral with the 4x4 turned off then hitting the 4x4 LOW button. Could someone explain to me why it would be beneficial to doing something like that?l Thanks

Pulling power, much more torque in 4x4 low... why you'd need 2x4 low over 4x4 low I don't see any benefit. Unless you had great traction already with the rear wheels and were pulling something.. like a boat on a slip... but 4x4 would be better in that situation too.

 

[Limited02]

P. doggy states that you can put it in 2x4 low by putting it in neutral with the 4x4 turned off then hitting the 4x4 LOW button. Could someone explain to me why it would be beneficial to doing something like that?l Thanks

Let's clarify...

Putting it into neutral and pressing "4x4 Low" puts you into 4x4 Low, not 2x4 Low. Also, the ONLY way to put it into 4x4 Low is by first putting it into neutral

The ONLY way to get 2x4 Low, you will need to have the driveshaft removed, put it into neutral and press 4x4 Low.

If we had manual locking hubs, we could leave them unlocked, press 4x4 low and we'll end up with 2x4 Low(because hubs aren't locked) We don't have manual locking hubs, so that's not an option.

In short, 2x4 Low isn't possible without the driveshaft removed.

The advantage's would be if you were on dry ground and needed that extra grunt or wanted to move a heavy load slowly up a hill/or down. It's not a good idea to use 4x4 on dry pavement, that's when 2x4 low could be handy.

 

[xTOM153x]

I did the BWM today and I tried the 2x4 Low and you have ridiculous amounts of power its crazy. My rear tires were screeching on dry pavement flooring it off a straight line. Also it makes it a lot more convenient to turn the 4x4 off instead of having to go and remove the fuses! Thanks for the post it helped a lot with installation!!

 

[Limited02]

I did the BWM today and I tried the 2x4 Low and you have ridiculous amounts of power its crazy. My rear tires were screeching on dry pavement flooring it off a straight line. Also it makes it a lot more convenient to turn the 4x4 off instead of having to go and remove the fuses! Thanks for the post it helped a lot with installation!!

Okay, so I was wrong?

I'm trying to picture how you can go to 4x4 low without making the front driveshaft turn. Is there more than one motor on the xfercase? Hmmmmmm...

 

[Curtis]

Okay, so I was wrong?

I'm trying to picture how you can go to 4x4 low without making the front driveshaft turn. Is there more than one motor on the xfercase? Hmmmmmm...

Im with you, I assumed even with the BWM done, if you put in 4x4low the front wheels are still gonna have power.
And besides, the gearing is so low in 4x4 low I seriously doubt you could screech wheels

I thought the only thing the BWM did was prevent automatically shifting into 4x4high


Here's a picture I found that similar to our Explorer transfer cases.
Notice the round mount where the shift motor is located. With the shift motor off, you can manually turn the shaft inside and put the case in 2wd, 4wd and 4wdlow
The BWM basically disconnects the automatic signal to the shiftmotor.
Beyond that if the motor does shift to 4x4low, as Limited02 above said you're gonna have 4wdlow not 2wdlow.
I dont know what you were "screeching" but it could not have been just the rear wheels

 

[IZwack]

Okay, so I was wrong?

I'm trying to picture how you can go to 4x4 low without making the front driveshaft turn. Is there more than one motor on the xfercase? Hmmmmmm...

Thats the point - 4wd engagement is physically independent and has no physical connection (in terms of actuation) with LO or HI range. 4wd engagement is electrically actuated by an electromagnetic ring sitting inside the transfer case (to which the "brown wire" is hooked up to) - which is separate from the shift motor. This electromagnetic ring and the shift motor are therefore only "connected" or "associated" with each other through the electrical circuit. Once you do the BWM, you pretty much isolate the electromagnetic ring from the shift motor.

 

[jleehoyle567]

so has anyone attempted to do the BWM on a mountaineer with AWD? as of now i have my front shaft removed but would like an option instead of just 2wd.

and what is the point of the relay if its just off and on? i cant see a downside to the relay but not perfectly clear on its purpose.

 

[Limited02]

so has anyone attempted to do the BWM on a mountaineer with AWD? as of now i have my front shaft removed but would like an option instead of just 2wd.

and what is the point of the relay if its just off and on? i cant see a downside to the relay but not perfectly clear on its purpose.

An AWD is just that, full-time 4x4. You can't make it 2wd unless you take out the driveshaft.

For the relay, if you are referring to the on/off switch it's used to turn off the "Auto 4x4" that occurs when the rear wheels slip on an Autp 4x4 Ex or Mounty. There were two 4x4 options available, Auto and AWD. The Auto will cruise around in 2wd and when the rear wheels start to slip, the front will engage to help out. With the switch, you can turn off the auto part and the rear wheels will continue to slip, resulting in a burnout or hitting a tree

 

[D Hook]

I would be happy with just a light that tells me when the 4x4 has auto-engaged and when it's kicked off again. This last weekend, I was on a gravel road. I stopped to pull out onto the highway and spun the tires on the gravel, kicking in the auto-4x4. But I couldn't tell if it went back to 2x4 when I got onto the highway. It FELT as if it was still in 4x4 and was worried I'd do damage to the T-case by driving on dry pavement with it engaged. If there was a light that came on whenever the 4x4 auto was engaged, it would be a big help. That way I'd know it had auto-disengaged after determining there was no more wheel spin detected.

Anyone know how to rig an indicator light like that?

 

[IZwack]

Tap the infamous "brown wire" to a relay and then drive an indicator (12v LED?) from that relay. If the signal is pulsed, you might have to use a solid state relay (to get rid of the annoying clicking) and then a capacitor (after the relay) to buffer the voltage.

 

[D Hook]

Do you think it needs a relay? Is it pulling that many amps?

 

[Limited02]

I would be happy with just a light that tells me when the 4x4 has auto-engaged and when it's kicked off again. This last weekend, I was on a gravel road. I stopped to pull out onto the highway and spun the tires on the gravel, kicking in the auto-4x4. But I couldn't tell if it went back to 2x4 when I got onto the highway. It FELT as if it was still in 4x4 and was worried I'd do damage to the T-case by driving on dry pavement with it engaged. If there was a light that came on whenever the 4x4 auto was engaged, it would be a big help. That way I'd know it had auto-disengaged after determining there was no more wheel spin detected.

Anyone know how to rig an indicator light like that?

I'm not sure at the rate it should disengage, but when driving in the winter with 4x4 auto, I would say I can feel the transfercase engage/disengage about every .5 seconds when spinning the tires. That's why when I know I'm going to really be needing 4x4, I just put it into 4x4 high.

I really doubt it was still in 4x4, but if it was, you need to solve that problem first