Okay, I'm experiencing a weird situation with my 4Runner. Whenever I'm driving at a higher rate of speed and I hit my right blinker, the RPM's jump slightly and kicks the cruise control off. If I hit my left blinker with the cruise on, my RPM's twitch but it stays on. With the cruise control turned off, the RPM's jump slightly with a left or right blinker. I originally thought it was a short with the headlight/blinker stalk because the stalk had broken off and was hanging by the wires. However, I replaced it a few days ago and still have the same problem. Any thoughts?

Anyone? Noticed today that it's not just while the cruise is on. If I'm cruising around 80 or so and I hit the blinker either way without taking my foot off of the gas...the RPM's jump a little bit. Not sure what's going on. Bad ground somewhere perhaps? I've seen some funky things happen in regards to a bad ground.

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Did the problem start when you broke the stalk? If not it might be a spiral cable issue. Does your horn do anything funky?

The switch was already broken when I bought it last year. It had been glued back together. The glue finally gave way about a week ago. I replaced it with a brand new switch/stalk from Rockauto. Probably one of the easiest repairs I've ever done btw! The horn acts normal. Nothin funky happens when I honk it sitting still, or at speed.

Ok so has the problem been there since you bought it? I would think it has something to do with the stalk. The spiral cable usually affects the horn and cruise but I would think the turn signals are separate.

Yes, it was like that when I bought it. I just changed the entire stalk out though, so it shouldn't be that. The RPM's still jump a little bit even with the cruise off, when the blinkers are activated.

I don't know. It sounds to me like something is shorting in there and activating part of the cruise system.

It definitely has me baffled.

Not sure if it is the cruise or not. Today I was driving around 70 without the cruise even turned on. I hit my flashers to thank a truck that had pulled over to the shoulder to let me pass, and I still noticed a slight jump in RPM's. It's not like it's taking over the speed of my 4Runner or anything...just a very slight twitch in RPM's. The only aftermarket things I have are a plain Jane Pioneer radio, supercharger installed from the dealer when it was first purchased, a 3" OME lift, and LED tail lights.

Before reading all of this, try switching out the LED's for incandescent and test it.

I had a similar problem in my Gen 3 this fall. Cruise control disengaged when I put on a turn signal. This may be like yours, but it may not. My apologies, I would make my response more concise if I had the time.

Quick summary of my solution: bypass the electronic towing package if you have one and check for burnt out or dim lights in the rear of the vehicle. Replace LED tail lights with regular incandescent or high wattage LED's that better match the impedance of incandescent lights.

Here was my problem and solution:

Once upon a time, I had a working electronic braking system. It's an add-on towing package that engages brakes, turn signals, and brake lights on a trailer when I tow with my 4Runner. Then, I towed a trailer that was mis-wired, and my brake controller caught fire and failed. Several years later, a short developed between the turn signals and the brake wiring in the towing package. When I changed lanes while the cruise control was engaged, the cruise control would disengage when I turned on my turn signals or caution lights. This is where it gets ridiculously complicated.

The electrical short passed a low voltage (~6 Volts) from my turn signals to the towing package's brake system. The electronic brake controller would activate and trip the cruise control's brake sensor, so the cruise control would be disengaged. The brake controller actuated with the blinking of the turn signals. In addition, the electrical short caused the 4Runner's red LED brake lights (not the running lights/circuitry) to flash in sync with the turn signals. The right turn signal caused both of the LED brake lights to flash. The left turn signal only caused the right brake light to flash, unless the right turn signal light was unplugged. If the right turn signal was unplugged, then both brake lights would flash in-tandem with my left turn signal. There was some weird electrical black magic happening then.

After three weeks of trouble shooting, I deduced the short was between my right turn signal and the braking system. By powering the right turn signal with an independent power supply, I was able to replicate the failure. Unfortunately, that power supply had enough current that a loud "POP" was heard when I turned it on. I'll get back to that later.

After the "pop," the ABS failed and was no longer functional. Turns out that the ABS system turned off to warn me that my cruise control had somehow failed. However, after the brake controller was removed, the cruise control worked flawlessly and did not disengage when I turned on either of my turn signals. The cruise control properly disengaged when I hit the gas pedal or the brake pedal. The cruise control was now normal. The ABS was dead.

Ironically, the ABS system turned on again if the cruise control was unplugged. Because of my independent power supply stunt, I somehow damaged the cruise control with the electrical short that traveled from the right rear turn signal through the rear towing package to the dashboard electronic brake controller into the cruise control's brake sensor. Technically, the previous sentence isn't a run on. Anyway, back on topic. To figure that last bit out, it cost me $600+ parts and labor for a mechanic to fix what I screwed up by fixing my turn signal-disengaged-cruise control problem. If my LED 7440/7443 tail lights were not dimming/dying of old age, my cruise control probably would not have failed during my testing.

Moral of the story? Replace all tail lights with C5 Cree (no SMD's) or incandescent bulbs and bypass the electronic brake/towing package if the cruise control disengages with the activation of the turn signals.

Watch the little red LED flash on the dashboard tow-package brake controller. It normally flashes when the driver applies the brakes. It flashed in sync with the turn signals, helping to reveal the electrical short.

Wheeew...black magic for sure!! This would have been an easy solution a few weeks ago, before I sold my other 4Runner! I'll try tracking down a set of tail lights to see if that alleviates the problem. I didn't install these lights...the P.O. did. Not sure what brand they are. They could very well be cheap, Ebay components. Thanks for taking the time to explain that!

Any word on your diagnosing the problem?

No such thing as electrical black magic! While I admire your perseverance in solving your own problem, I don't see how it relates to the OP's problem. Other than the Cruise kicking out, I'll give you that. Maybe the OP can clarify if he has a brake controller. His main question I thought was the bump in RPM.

Now the stop light switch does trigger the ECU, which in turn shuts down the cruise, not sure how that could work backwards from the brake controller. I have had many brake controllers and even in a dead short they have been protected from back feeding the vehicle. But that's irrelevant if the OP has no brake controller.

The poor quality bulbs could be a stretch, but strange things do happen. It just isn't magic.

Similar issue I had after adding the tow harness into tail lights. Anytime turn signal is switched it will engage and disengage into overdrive at the rate of the turn signal and will also kick off cruise control until pressed to resume.. I do have the LED Tails so not to say that could play into it.. Just don't remember it doing it before hand...Anyway maybe I will unplug it and see or swap the tails back and check. If anybody else has this issue or fix please chime on