I have an 2008 Isuzu i290 (essentially the same thing as a Chevy Colorado). I bought it new in '08 and it’s had (mostly) regular maintenance.
There was a recall for the brake lamp switch for Isuzu i290’s a while back. In addition to brake lights not working correctly with the faulty switch, the switch also affected people’s cruise control (the CC just stopped working completely when the switch went bad). I replaced the switch about a year ago and have not had any trouble with the cruise turning on since. My brake lights work fine and my cruise turns on with every attempt, so I don’t believe the switch is bad.
However, recently my cruise control has started randomly shutting itself off. I can immediately turn it back on and it will work for a random amount of time before shutting off again. I commute to work, so I do most of my driving on highways in 4th or 5th gear, and this is when I generally use cruise control. I don’t know if it’s only shutting off in 4th and 5th gear, or if it would also shut off in lower gears. Sometimes I can drive the 50 miles to work and it works perfectly, and sometimes it might turn off as many as 4 or 5 times. It seems to happen more when I am going uphill, but it sometimes occurs on flat areas. I don’t recall it happening on a downhill slope, but I couldn’t say it’s Never happened. I tried shifting to 4th to increase the RPM’s when going uphill, thinking perhaps they were too low as the engine worked to pull the truck up the hill, but that hasn’t made any difference. Also the amount of fuel in the tank doesn’t seem to matter.
I know I’m not accidentally bumping the brake or clutch, since I started paying close attention when it started happening and I am certain it’s not the cause.
Can anyone please advise on what may cause the cruise control to randomly shut off but then have no trouble turning right back on? Thanks!