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2002 Chevy z71 cruise control problem

Roadkill4twenty

By Roadkill4twenty
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Roadkill4twenty New Member

Roadkill4twenty

Posted
Posted

So I have an 2002 Silverado Z71 1500 (automatic trans) and a while back the cruise control stopped working literally 20 minutes before my transmission blew out. I've read that transmission problems can cause the cruise to stop working but I'm having trouble determining if that's THE cause. Long story short, I got the transmission fixed and my truck running again but still no cruise. Checked fuse and its good. I took it to Autozone and had it checked for codes and nothing. I also checked the brake light switch and it's working as it should and replaced the speed sensor while I was reinstalling the transmission. So I guess I'm just trying to figure out if it's the cruise control switch on the steering column that's bad or the cruise control module (which I have replaced a few years ago due to the servo cable breaking), or something else so I'm not wasting money on parts that I don't need. Thanks for the help!

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Time to beg and borrow a bi-directional / high end scan tool. That will be a huge help in determining what is missing. If the computer doesn't SEE that the brake light switch is working (or, it sees that it's applied when it isn't) then cruise will never work. Same with the speed sensor - if reading 0 mph all the time, then cruise will never activate. Super easy to check with a good tool. Even regular lower-end tools should have this capability by now, I would think.

 

Doesn't have to be bi-directional - just needs to have the capability of seeing ALL parameters in ALL modules. Go into the inputs section and watch what happens when you press the brake - if it says, APPLIED, when you hit the brake, then the ECU is seeing brake application normally. You can also press all the steering wheel buttons to see if that's all working, too. Saves a TON of time over physically dismantling things and testing. These days the dismantling part can take hours sometimes ...

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