2003 Chevrolet Avalanche 1500 Q&A

2003 Chevrolet Avalanche 1500 Question: abs and brake lights come on whenever i go over a small bump ..please help..

abs and brake lights come on whenever im going over a small bump or pot hole it also says to service brake system when i already serviced the brakes... my speedometer isnt working also..i dont know what it could be please help....... -
Answer 1
also having problems reduce engine power light coming on and the a/c going off -
Comment 1
My 2004 Avalanche is doing all of these things as well. The dealership is telling me I need different modules replaced but I'm not convinced. All of theses things go hay wire at the same time and only when I hit a bump in the road. Any solutions? -
Comment 2
I have a 2002 Avalanche and my ABS and Brake light come on when I hit a bump or just driving. I had a diagnostic test done and was told I needed to replace the ABS switch module. -
Comment 3
Hi, I'm having the same problem you all described, to a point that I can't really drive it anymore. Has the problem been fixed for any o you? Mine (at 2004) has been in the dealership for a while and they can't figure it out... I'm pretty scared to see the final bill and a nil diagnosis! -
Comment 4
i have a 2002 avy and have gone thru all thats been said on this site.have been told its my ground wire in back of intake manifold.have checked it and appears to be good however there is a lot of dirt and grease on it.don't know if that makes a difference.am in the process of putting a ground wire from frame to engine block in hopes that could be a fix.am also taking my starter down and cleaning up,a lot of corrosion on terminals.there appears to be a ground on it also.so thru all this talking with a lot of people its a ground issue.hope this helps. -