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Code B2725 Help me

I know this post is old but I have to respond since I've figured out something that may interest others that are willing to tinker....

I was receiving this B2725 code intermittently.  Some days I would get the "service 4wd" but it would always go off upon restart.  Other days I never saw it.  I had the opportunity to review this web site as well as have my cousin scan my truck with a 'proper' $scan$ tool.  The only code was this B2725.  I was originally  thinking I was looking at replacing of the shift servo or something REALLY expensive.  I read all the horror stories of what could be wrong and I didn't want to even mess with it.  My long time mechanic cousin convinced me so I reluctantly replaced the button control module (the buttons in the dash) for $70. 

In the process I also disassembled the 'bad' button unit.  Then I saw why I was getting the code intermittently in the first place.  I had to take the unit apart down to the circuit board using 4 or 5 screwdrivers to pop it.  Pretty easy but easier with a helper.  There are two plugs where the control wires connect to the button unit.  These connectors are soldered to the circuit board.  Around the pins of these connectors at the circuit board I noticed that the solder joints were all cracked around the pins.  It's very subtle and would likely not be noticed by someone that never seen this problem before.  They look like a hairline circle around the pin.  This is where the solder is cracked.  Cracks mean resistance changes and voltages drops; hence the "sevice" light.

I've seen this type of problem in my wife's 87 vette with an intermittent heater control.  There is too much and/or just the right amount of vibration to cause the solder around the pins of the plug headers to crack.  I applied some rosin flux to the cracked pins and reflowed the solder along with some new solder.  I'm not sure if I fixed the problem since I had already purchased a new controller but I likely have a repaired spare. 

I don't like the new unit.  The lights are very very dim compared to my original unit.  My mechanic cousin says he's replaced a couple himself with only this code showing.  He also noted the new ones have much dimmer lights.  I told him to save them and I could probably fix them.

After lurking on this forum for a while I'm sure there are a couple people out there that have had the same problem.  Several have noted replacing a couple over a period of 50K.  There is a TSB on this and it specifically says to only replace the control button unit in this case.  I would guess this nerdy repair would fix the problem for some. 

If anyone has just this code you can probably fix this.  I takes less than 30 minutes start to finish....if you can solder.  I could provide further pointers if someone wants to be a test bunny.  NOTE this fix is likely only good for those that have the B2725 code.  If you have additional codes or C codes you are probably looking at a problem related to the shift module.  My mechanic cousin has also replaced many of those units. 

I wish I took pictures....I was on vacation at the time so didn't have much time. 


Thanks. Glad I found this thread on code B2725 & I also got C0900. The scanner at a near by advance autoparts pulled these up today. Drove there after work. This morning hwy driving 65mph the truck became possessed all at once, the DIC flashed park assist, D light alternated back and forth to P then stable track light popped on, door locks were locking & unlocking continously, nav clock screen went dark, a.c. came on, I slowed down to 45mph as approaching local Rd to work to see if I could hear or feel a loss of power. Not. Proceeded to hit all the buttons on and off and it resolved. The running boards didn't come out when I opened the door I turned the key pushed that button an they extended. I think I've got other issues going on. Any thoughts? I'd appreciate it.
I'm do for a battery getting it before winter but that's the least of my problems. Not mechanically inclined
Thanks for any feedback