http://thumbs4.ebaystatic.com/d/l225...mhL72Iuieg.jpg

side note, i didnt want to tear the ground wire apart to put the new sensor on so so i unbolted the small body ground next to the battery to slide the sensor on it, when i unhooked the ground i lost all power in the car, this seams odd to me, shouldn't the heavy wire still ground the system to keep all the electrical systems alive?

 

keep us updated... i have all the same problems got a new abs module didnt fix my problem... i noticed on nice warm days my lights go out idk why

 

If you are disconnecting that small gauge wire off the negative cable and all systems go flat you have a problem. There are literally dozens of components relying on proper grounds.
Go through this thread and remove clean, coat (die-electric grease) and re-secure all the Gxxx connections
http://www.gmls4.com/index.php/topic,1412.0.html

 

was having the same issue as you for at least the last year on and off. I have now had my battery current sensor unplugged for 2 months with no issue of the brake lights going out. Mine has a burn hole in the bottom that i could only see if i took it off the battery. After looking at schematics the sensor goes back to the bcm which as we know controls the systems in question.

hope this helps.

 

It sounds like you might be having a little different issue than me. But for my .02, I am getting the same warnings on the dlc. I believe it is my wheel bearing. I replaced the one side last summer and since I was parking it soon I didn't do the other side since it had some life left on it too. The sensors for all traction control, abs are all in the wheel hub. And these cars seem to be pretty hard on them.

 

The Battery Current Sensor on my 2008 LaCrosse Super developed the famous "hole" in it by rubbing on top of the battery. It suddenly turned off ESP and TC, and set the ABS MIL. I also lost my brake lamps altogether and the DIC was so dim I could no longer read what it was saying in the direct sunlight. Of course none of the service information at alldatadiy was helpful, even as related specifically to the C0161 code that was set. I searched online and found this thread that tipped me off about the BCS.

Here is the really sad/stupid part.... in the process of confirming the BCS as the cause, I unplugged the 3 pin connector so I could confirm whether mine was 5V or 10V by measuring (it was 10V), then I noticed that the ESP and TC were restored with normal ABS, DIC, and brake lamp function.

So in summary... GM takes an apparently common failure mode of the BCS and then arbitrarily forces the car to be unsafe to drive by turning off the brake lamps, diminishes ABS function (it did very weird things on panic stops during the intended failure mode), shuts off ESP and TC, makes the DIC unreadable, then fails to list BCS as a possible cause in the service info for C0161. That way the owner either takes the vehicle to a dealership or repair shop that might not be able to diagnose the problem, with likely repair bill in the $100s of dollars for what in the end will be a $21 part, often with problem returning due to misdiagnosis, then they wonder why they went bankrupt.

I drove the vehicle ~200 miles with the BCS unplugged before replacing it and the only symptom I could find during that 200 miles was that the charging voltage was fixed at 13.4V. Thanks for helping me solve my problem, and for letting me vent.

 

ive had the same stupid idiot lights and dic cautions for months now and have been reading that the abs module could be the culprit... where is said sensor so I may remove immediately and see if that's the cause of anger everyday..

 

It is attached the front of the ABS pump, it looks like this. You can send it out to module master for testing and repair. Otherwise I think they are like 800-1000 bucks new.