My gfs Pontiac Montana has the abs, traction control and even the hand brake light come on. It was once in a while but now it's getting more frequent. The codes that came up are c0035, c0036, c0040, c0041, c0050 and c0281. Does anyone have any clue what it can be or where do I start with this problem?
You might suspect the generator putting out low voltage, high ripple, or voltage spikes. Unplug the small connector but be sure the battery is fully charged first. If the problem doesn't show up, suspect the generator, but to prevent a repeat failure, replace the battery too. The battery dampens and absorbs those harmful voltage spikes. They lose their ability to do that as they age.