2008 4 cyl 2WD Cruise Control Hiccup

Last week, when tapping 'cancel' the cruise control didn't disengage. It took a brake tap to release it.

First thought is maybe the vacuum tubes are starting to wear out. That is what happened to an old car years ago.. I'm not even sure how the system works on this, to be honest. It's the only manual I've had with cruise

What should I check? Or is this beyond backyard repairs?

It hasn't done it since

 

Vacuum hasn't been used to run cruise control since... like... the late 90's? Maybe even mid '90s? It's been at least partially electronic on just about everything in the last 25+ years, and since 2nd gens have electronic throttle bodies, it's all electronic. Button tells ECU to hold speed, ECU tells throttle to open or close (and for automatics, shift)

It's obviously not totally inop if it sets, and then releases upon braking. So my best guess would be the cruise switch. Someone just posted the wiring diagram for it the other day, and I believe it's all done with 2 wires through the steering wheel, and the switch varies resistance on the wires, which should rule out the spiral cable being faulty.

 

@fb40dash5 is correct, the cruise is built into the PCM programming. When the cruise is set the PCM controls the throttle directly. The cruise switch operates by changing the resistance between the control wire and ground, each function of the switch has a different resistance value.

If all the other buttons except cancel work normally I would suspect the switch, if the buttons all work intermittently I would suspect the clockspring.

 

Replaced my switch about a year ago. When I would push the button to engage cruise control, the light would light on the dash however nothing would happen. Replacement of the switches real easy and quick. Works perfect ever since.

 

The switch may be failing. I had cruise control installed in my base 2010 RC 2WD, and within a month it was only working when it felt like it. Over a year later, my mechanic swapped out the OEM-style aftermarket for an OEM switch I had lying around and it's worked fine ever since. I have no idea what was actually wrong with the switch, but the green "CRUISE" light would turn on, while the cruise control itself wouldn't engage.

 

By the way, anybody on here living in Philly or the surrounding suburbs, DO NOT go to H&R Radio in Warminster, Pennsylvania for any reason. They butchered my truck to the tune of about $700 in damage when tasked with installing cruise control, lying and telling me that I had to bring the truck to a Toyota dealer to get it activated when they knew full well they'd busted the clockspring and wheel position sensor; I stupidly brought the truck to the dealer thinking it was a simple fix, and they discovered the aforementioned broken parts. I went back to confront the guys at H&R with my dad in tow, and we even heard the owner screaming at the guy who did the install, but he of course denied it. I'd mentioned to the owner of H&R that my mechanic has attempted to install cruise control in December 2020 prior to me bringing it to them in March 2021, and they used it as ammo against me.

"You brought it to your mechanic and he opened up the steering wheel, so how do we know he didn't break it?"

I know my clockspring wasn't literally snapped before I brought it to you guys, not to mention that your guy didn't put the dashboard back together correctly and also snapped a tab on the steering column casing. FUCK YOU.

My mechanic who you were so eager to blame for damage that you caused ended up fixing the damage that you caused! He also swapped out the defective OEM-style Rostra switch for the OEM one that I originally bought at the dealer.

 

Also, my truck is automatic, but I've been told that stick shift Tacomas with cruise require an extra wire between the cruise control stalk and the clutch start/cancel switch or something...? Maybe this could be the problem?!?!

 

I can't imagine why they'd run another wire to the switch for that, not like they do the same for the brake light switch AFAIK, and the top clutch switch (which is used to disable cruise, different from the lower switch that engages by the floor to enable starting) would be performing the same function as far as the cruise is concerned.