Just an FYI. Mine did that last week off-roading in Nevada. I was going down a hill, hit the brakes and all of a sudded the HDC, ABS and TC lights lit up. I've had this happen before but usually shutting the car off and re-starting got rid of it. This time it has not gone away. Even after over a week of driving around.
I decided rather than replacing $5000 dollars worth of parts before I found the problem that it would be better to go to the dealer and have them hookup the test book.
They cleared the codes and screwed around with it and test drove it around several times and never could get the lights to come back on. I'm not saying it may not happen again, but for now that's all it seems to have taken and no parts had to be replaced.
I'm thinking a goofy set of conditions, dirt or a rock, or when my air bag blew, may have caused something to setoff the computer and I'm hoping that's the end of it.
Also FYI, even though all these lights were on and I didn't have HDC or ABS, funny I could hear the traction control working the rest of the trip, which is wierd but true. Must be some failsafe built into it.
FYI I also replaced the air bags with springs as noted on an earlier post. The dealer re-programmed the computer so it now knows I have springs and not SLS so no light for that and the air compressor wont' run anymore. I also have 1 good air bag for sale if someone wants a spare so you don't blow one in the boonies and wonder how you'll get back with a lowrider Disco.