Mystery cruise control problem.

Just got my Taco (06 v6 4wd trd-OR) last Saturday, tested the cc during the test drive. On Sunday the cruise stopped working, the light doesn't even turn on. I've checked the brake switch, the cc lever, both still work and don't have any lights or fuses out.
No clue where to look next. Suggestions?

Edit: It appears the previous owner had a brake controller installed, not sure if he could've affected something when he took it out.

 

Make sure he took it out cleanly. All it takes is one wire, stripped on the end, flopping around. And finally finding a permanent home against a good ground.

 

It appears he did, my truck has the factory towing package and the flat 4 connector and pigtail harness are both in good shape. If he hacked in somewhere else, it's not obvious. I can get my hands on a scanner when I'm back in CO, I was just hoping to take care of this before driving back from NC. This is getting extremely frustrating, with all the usual suspects functioning normally.

Can anybody point me towards the other connectors involved? Cruise unit, ecu, anything....

 

If the truck has the towing package, the controller harness is all plug and play, so there shouldn't be any loose wires. The truck when new would have had Toyota's adapter connector to plug in under the dash but that's probably gone with the brake controller. That is, unless he was goofy and cut the wires on that, and never took the plug out.

It's not hard to take the steering wheel apart to put a multimeter on the cruise stalk. Just a few torx screws. Stay clear of the yellow airbag wiring though, and it would be a good idea to disconnect the battery for this. The cruise stalk IIRC has only two wires which is strange considering it has four actions.

Something else to consider is that it might be the clockspring. It wouldn't be the first one of those to fail (there was a recall years ago). Does the horn work?

There's no cruise unit. Cruise control is a program in the ECU because of the throttle-by-wire system. Makes it seem silly how they offer the base model trucks have no cruise when literally all they're lacking is the stalk on the steering wheel, sometimes the wire from the clockspring to the ECU, and if applicable, the clutch switch. At least it's easy to add it in later.

 

When you say the light doesn't turn on, are you talking about the dash light that reads "Cruise Control" when you push the Cruise Control ON button at the end on the stem? If that light is not turning on, then I would think you are not getting any power. I would double check the fuse. Take it out and replace it with one you know to be good. Sorry for lack of advice on this. I don't think it is a common problem that comes up.

 

The previous owner was nice enough to cut off the harness and leave it in the glove box.

I've already put a meter on the stalk, it just works on a set of resistors in series, everything worked and so does the horn. I started getting error 3 on the cd changer after I reconnected the battery though, I tried resetting it again, now it doesnt even recognize that there's a disc inside. Luckily I wanted to upgrade the HU anyways, so I won't worry about it too much.

Yes, I mean the dash light. Unfortunately there's no one fuse and the rest of the dash lights work, but for lack of other options I'll double check them.

Should the cruise light come on with the others before the car is cranked? It doesn't, so now I'm wondering if the LED just stopped working for some reason.

Here's the wiring diagram.

 

Check the trailer wiring harness itself, my CC acted funny when my harness went bad.

 

I thought the factory tow package had the 7pin round connector?

 

In the back, yes, but there's two other harnesses by the fuse box under the steering wheel for a brake controller.

 

Did you figure it out? having same problem and now that I see a diagram I'm diving in...