BWM Brown Wire Mod 3rd Gen

[obrec1]

4x4 Hi light on with bwm

I did the BWM and every things workin like it should except when spinning the rear tires in 2WD mode the 4x4 High dash light comes on. Wondering if anyone else has this problem

 

[Limited02]

I did the BWM and every things workin like it should except when spinning the rear tires in 2WD mode the 4x4 High dash light comes on. Wondering if anyone else has this problem

Could just be the auto 4x4 trying to kick in and it's letting you know. I'd say it's nothing to worry about.

 

[93explodersport]

so the power cord (the red one) is a wire from the existing 4x4 harness??

 

[93explodersport]

well. i did the mod to my 02xls and now no 4x4 works. do you need the red power? i just ran the wires through a switch, one in and one out and one to the ground, same switch used in origional pictures. what is the problem, grounded to a good solid ground, all wires tightly fastened, just that the light does not light up. do i need the power supply? i turn the switch on and no 4x4 will engage but the lights light. and i turn it in the off position and the game thing happens. i would think that the light does not matter if its on just as long as the switch is in the on position. do i need a relay? please help!!!!!

 

[RickyRider]

well. i did the mod to my 02xls and now no 4x4 works. do you need the red power? i just ran the wires through a switch, one in and one out and one to the ground, same switch used in origional pictures. what is the problem, grounded to a good solid ground, all wires tightly fastened, just that the light does not light up. do i need the power supply? i turn the switch on and no 4x4 will engage but the lights light. and i turn it in the off position and the game thing happens. i would think that the light does not matter if its on just as long as the switch is in the on position. do i need a relay? please help!!!!!

I did the mod on my 02XLT a year or so back and it worked great.
I did use the relay so I would have an indicator light when I had the brown wire in its factory state of being connected together.

If you do not need the indicator light you can just running it through a standard on/off switch rated for 25 or 30 amps at 12 volts. There should be two terminals on the back of the switch. The two ends of the cut brown wire go to these two terminals.
There is no ground involved.
When you cut the brown wire you have turned your 4x4 into a 2x4.
To turn it back into a 4x4 you just need to have your on/off switch reconnect the brown wire.
The switch can be mounted in metal or plastic as there is no ground involved.

Hope that makes it clearer.

 

[93explodersport]

there was a third terminal on the back of the switch, if i have the 2 ends of the brown wire going to the wrong terminals would that do it? im going to now use a relay to see if i can make it work, the red power cord is coming from the existing 4x4 harness. does it need to be cut from the harness or how does that work out?

 

[ryno_rx8]

so why could you not just disconnect the Auto 4X4 switch and it work that way? Wouldn't it be in 2X4 until you pressed the 4 high switch? I haven't tried it so i don't know but just curious.

 

[Rofocowboy84]

so why could you not just disconnect the Auto 4X4 switch and it work that way? Wouldn't it be in 2X4 until you pressed the 4 high switch? I haven't tried it so i don't know but just curious.

No, you need to disconnect the sensor. Plus, if the switch was disconnected, the first time you put it in 4 High, you wouldn't be able to put it back into 4 Auto... The 4 Auto switch is more of just a "standby switch", the system is automatically in 4 Auto, unless, like I said, you bypass the sensor/computer.

 

[RickyRider]

there was a third terminal on the back of the switch, if i have the 2 ends of the brown wire going to the wrong terminals would that do it? im going to now use a relay to see if i can make it work, the red power cord is coming from the existing 4x4 harness. does it need to be cut from the harness or how does that work out?

Your switch with three terminals is likely a SPDT (Single Pole Double Throw which is on one way and on the other way).
You only need a SPST (Single Pole Single Throw which is on one way and off the other)

Your SPDT will work just fine if you connect one of the brown wires to the middle and the other to one of the ends. The terminal at the other end of the switch would not have anything hooked up to it. This turns your on - on switch to a on - off switch which is all we need.

There is no need for the whole relay business unless you want an indicator light to turn on next to your switch.

Some switches have an indicator light build in. My switch has a tiny red dot indicating I am in 4X4 mode. The switch is oriented so when I push the switch up the red light comes on and I am in the factory 4x4 mode. (Auto 4x4hi 4x4lo as per my factory switch)
I run 99 percent of the time with switch down in 2x4 mode. The 2x4 mode is great for backing my trailer up a steep driveway to its home.

I suggest you take your switch with nothing hooked up to it and check out what is happening with an ohm meter.

If you do not have a ohm meter handy you can try the following.
I trust you extended your brown wire ends up to behind the glove box / dash area. Just try to twist them back together and cover them with back tape. If this does not get your 4x4 back working you may have done damage by grounding the brown wire. Maybe a fuse got blown.

Try to diagnose the switch and the brown wire / 4x4 system as per above before you try the relay method. Then once it is working you can do the relay hookup if you still want to.

 

[93explodersport]

i installed the relay and all and it works like a charm! woooo!!!

 

[20Exploder02]

ok so i did the brown wire mod an works great but one thing. when im driving i can hear a whining sound coming from the transfer case an not sure what it is. any thoughts????

 

[20Exploder02]

and is there a way to switch it to 2x4 high instaed of using 2x4 low?

 

[93explodersport]

yes. with the switch off, press 4x4 high and you have 2x4 high

 

[Rofocowboy84]

and is there a way to switch it to 2x4 high instaed of using 2x4 low?

Um.....2x4 high is what it's normally in.....it's the same thing as 2wd....

 

[Opera House]

"standard on/off switch rated for 25 or 30 amps"

This myth continues......If I remember the clutch can draw no more than 2A. Still a lot of switches out there are pretty crappy imports that fall apart regardless of the current rating.

 

[jrfarve]

looks like a good idea, imma try it this weekend...

 

[fiveohwv]

fuse panel switch

If we know which fuses disconnect the transfer case, why not put the switch in those wires? Instead of chasing the brown wire all over the truck.

 

[JDT]

Has anyone had any negitive effects, like transfer cases dieing. Thinkin about doin it but I don't wana have to replace expensive stuff (except tires)

 

[Limited02]

If you don't do LONG burnouts and don't do them every 5 seconds, you'll be fine.

 

[aceniceros]

ok im thinking about doing this but there are a lot of information scattered around about the buttons and what they will do...

so ther is

4x4 auto
4x4 high
4x4 low

now i know what these are but if you do the bwm mod what will they do when you turn on the switch and when you turn off the switch...